The C# PDF Library

HTML to PDF

using IronPdf;

// Disable local disk access or cross-origin requests
Installation.EnableWebSecurity = true;

// Instantiate Renderer
var renderer = new ChromePdfRenderer();

// Create a PDF from a HTML string using C#
var pdf = renderer.RenderHtmlAsPdf("<h1>Hello World</h1>");

// Export to a file or Stream
pdf.SaveAs("output.pdf");

// Advanced Example with HTML Assets
// Load external html assets: Images, CSS and JavaScript.
// An optional BasePath 'C:\site\assets\' is set as the file location to load assets from
var myAdvancedPdf = renderer.RenderHtmlAsPdf("<img src='icons/iron.png'>", @"C:\site\assets\");
myAdvancedPdf.SaveAs("html-with-assets.pdf");

using IronPdf;

// Disable local disk access or cross-origin requests
Installation.EnableWebSecurity = true;

// Instantiate Renderer
var renderer = new ChromePdfRenderer();

// Create a PDF from a HTML string using C#
var pdf = renderer.RenderHtmlAsPdf("<h1>Hello World</h1>");

// Export to a file or Stream
pdf.SaveAs("output.pdf");

// Advanced Example with HTML Assets
// Load external html assets: Images, CSS and JavaScript.
// An optional BasePath 'C:\site\assets\' is set as the file location to load assets from
var myAdvancedPdf = renderer.RenderHtmlAsPdf("<img src='icons/iron.png'>", @"C:\site\assets\");
myAdvancedPdf.SaveAs("html-with-assets.pdf");

PM >Install-Package IronPdf

Install-Package IronPdf

MIGRATION GUIDES

How to Migrate from Ghostscript GPL to IronPDF in C#

Curtis Chau

Updated: August 1, 2026

Migrating from Ghostscript to IronPDF moves your .NET PDF workflow off command-line process spawning and string-based switch manipulation onto a typed, IntelliSense-enabled native .NET API. This guide walks through a step-by-step migration path that removes AGPL-3.0 licensing exposure and the external native binary dependency.

A note on terminology: Ghostscript (by Artifex Software) is dual-licensed under AGPL-3.0 or a commercial license, not plain GPL. The "GPL" tag is a long-standing community shorthand for the open-source build; everything in this guide refers to the AGPL-3.0 build of Ghostscript and the Ghostscript.NET wrapper (which is also AGPL-3.0 / commercial-dual). From .NET, Ghostscript is typically consumed via that wrapper, which P/Invokes the native gsdll32.dll / gsdll64.dll, or by shelling out to gswin32c / gswin64c via Process.Start.

Why Migrate from Ghostscript to IronPDF

The Ghostscript Challenges

Ghostscript is a long-standing PostScript/PDF interpreter from Artifex Software with decades of history. Its use in modern .NET applications presents several practical challenges:

AGPL-3.0 License Restrictions: Both Ghostscript itself and the Ghostscript.NET wrapper are dual-licensed under AGPL-3.0 or a commercial license from Artifex. AGPL's network-copyleft clause typically requires that you release the corresponding source of the larger work - including for SaaS / network use - unless you purchase a commercial license. This often rules out the AGPL build for closed-source or hosted .NET applications.
Command-Line Interface: Ghostscript is fundamentally a command-line tool. Using it from C# means spawning processes, passing string arguments, and parsing output - either via Process.Start against gswin*c.exe or via the Ghostscript.NET P/Invoke wrapper.
External Binary Dependency: You must install Ghostscript separately, manage PATH variables, and keep versions aligned across environments. Different native DLLs are required for 32-bit vs 64-bit (gsdll32.dll vs gsdll64.dll).
No Native HTML-to-PDF: Ghostscript cannot convert HTML to PDF directly. You first need to convert HTML to PostScript with another tool, then run Ghostscript to convert PostScript to PDF - a multi-step pipeline with external dependencies.
Complex Switch Syntax: Operations are controlled via command-line switches like -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=.... No IntelliSense, no compile-time checks.
Error Handling: Errors come through stderr as text strings, requiring parsing rather than structured exception handling.
Process Management Overhead: Each operation spawns a separate process, adding overhead and complexity for timeouts and resource cleanup.

Ghostscript vs IronPDF Comparison

Aspect	Ghostscript	IronPDF
License	AGPL-3.0 (network-copyleft) or Artifex commercial	Commercial with clear terms
Integration	Command-line process spawning	Native .NET library
API Design	String-based switches	Typed, IntelliSense-enabled API
Error Handling	Parse stderr text	.NET exceptions
HTML-to-PDF	Not supported (need external tools)	Built-in Chromium engine
Dependencies	External binary installation	Self-contained NuGet package
Deployment	Configure PATH, copy DLLs	Just add NuGet reference
Thread Safety	Process isolation only	Thread-safe by design
Modern .NET	`Ghostscript.NET` v1.3.x targets .NET Standard 2.0	.NET Framework 4.6.2+ and .NET 6/7/8/9
Async Support	Process-based	Native async/await

Migration Complexity Assessment

Estimated Effort by Feature

Feature	Migration Complexity
PDF to Images	Low
Merge PDFs	Low
Compress PDF	Low
PDF Optimization	Low
Encryption	Medium
Page Extraction	Low
PostScript to PDF	Medium-High
Custom Switches	Medium-High

Paradigm Shift

The fundamental shift in this Ghostscript migration is from command-line process execution to typed .NET API calls:

Ghostscript:  "Pass these string switches to an external process"
IronPDF:      "Call these methods on .NET objects"

Ghostscript:  "Pass these string switches to an external process"
IronPDF:      "Call these methods on .NET objects"

Text

Before You Start

Prerequisites

.NET Version: IronPDF supports .NET Framework 4.6.2+ and .NET Core / .NET 5+ (including .NET 6/7/8/9). Ghostscript.NET v1.3.x targets .NET Standard 2.0.
License Key: Obtain your IronPDF license key from ironpdf.com
Backup: Create a branch for migration work

Identify All Ghostscript Usage

# Find all Ghostscript.NET references
grep -r "Ghostscript\.NET\|GhostscriptProcessor\|GhostscriptRasterizer\|gsdll" --include="*.cs" .

# Find direct process calls to Ghostscript
grep -r "gswin64c\|gswin32c\|gs\|ProcessStartInfo.*ghost" --include="*.cs" .

# Find package references
grep -r "Ghostscript" --include="*.csproj" .

# Find all Ghostscript.NET references
grep -r "Ghostscript\.NET\|GhostscriptProcessor\|GhostscriptRasterizer\|gsdll" --include="*.cs" .

# Find direct process calls to Ghostscript
grep -r "gswin64c\|gswin32c\|gs\|ProcessStartInfo.*ghost" --include="*.cs" .

# Find package references
grep -r "Ghostscript" --include="*.csproj" .

SHELL

NuGet Package Changes

# Remove Ghostscript.NET
dotnet remove package Ghostscript.NET

# Install IronPDF
dotnet add package IronPdf

# Remove Ghostscript.NET
dotnet remove package Ghostscript.NET

# Install IronPDF
dotnet add package IronPdf

SHELL

Remove Ghostscript Dependencies

After migration:

Uninstall Ghostscript from servers
Remove gsdll32.dll / gsdll64.dll from deployments
Remove PATH configuration for Ghostscript
Remove any GhostscriptVersionInfo references

Quick Start Migration

Step 1: Update License Configuration

Before (Ghostscript):

Ghostscript under AGPL-3.0 requires either source disclosure under AGPL terms or a commercial license from Artifex.

After (IronPDF):

// Set once at application startup
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

// Set once at application startup
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

net

net

Step 2: Update Namespace Imports

// Before (Ghostscript)
using Ghostscript.NET;
using Ghostscript.NET.Processor;
using Ghostscript.NET.Rasterizer;

// After (IronPDF)
using IronPdf;

// Before (Ghostscript)
using Ghostscript.NET;
using Ghostscript.NET.Processor;
using Ghostscript.NET.Rasterizer;

// After (IronPDF)
using IronPdf;

Imports Ghostscript.NET
Imports Ghostscript.NET.Processor
Imports Ghostscript.NET.Rasterizer

' After (IronPDF)
Imports IronPdf

Imports Ghostscript.NET
Imports Ghostscript.NET.Processor
Imports Ghostscript.NET.Rasterizer

' After (IronPDF)
Imports IronPdf

Complete API Reference

Core Class Mapping

Ghostscript.NET	IronPDF	Description
`GhostscriptProcessor`	Various `PdfDocument` methods	PDF processing
`GhostscriptRasterizer`	`PdfDocument.RasterizeToImageFiles()`	PDF to images
`GhostscriptVersionInfo`	N/A (not needed)	DLL location
`GhostscriptStdIO`	N/A (use exceptions)	I/O handling
Process + command-line	`ChromePdfRenderer`	HTML to PDF

Command-Line Switch Mapping

Ghostscript Switch	IronPDF Equivalent	Description
`-dNOPAUSE`	N/A (not needed)	Don't pause between pages
`-dBATCH`	N/A (not needed)	Exit after processing
`-dSAFER`	N/A (default)	Safe file access
`-sDEVICE=pdfwrite`	Various PDF methods	Output PDF
`-sDEVICE=png16m`	`RasterizeToImageFiles("*.png", DPI: N)`	PNG output
`-sOutputFile=X`	`SaveAs("X")`	Output filename
`-r300`	`DPI: 300` parameter	Resolution
`-dPDFSETTINGS=/ebook`	`CompressImages(quality: 60)`	Medium quality
`-dFirstPage=N -dLastPage=M`	`CopyPages(new[] {N-1, ..., M-1})`	Page extraction (0-indexed)
`-sOwnerPassword=X`	`SecuritySettings.OwnerPassword`	Owner password
`-sUserPassword=X`	`SecuritySettings.UserPassword`	User password

Code Migration Examples

Example 1: HTML to PDF Conversion

Before (Ghostscript):

// NuGet: Install-Package Ghostscript.NET
using Ghostscript.NET;
using Ghostscript.NET.Processor;
using System.IO;
using System.Text;

class GhostscriptExample
{
    static void Main()
    {
        // Ghostscript cannot directly convert HTML to PDF
        // You need to first convert HTML to PS/EPS using another tool
        // then use Ghostscript to convert PS to PDF
        
        string htmlContent = "<html><body><h1>Hello World</h1></body></html>";
        string psFile = "temp.ps";
        string outputPdf = "output.pdf";
        
        // This is a workaround - Ghostscript primarily works with PostScript
        GhostscriptProcessor processor = new GhostscriptProcessor();
        
        List<string> switches = new List<string>
        {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}",
            psFile
        };
        
        processor.Process(switches.ToArray());
    }
}

// NuGet: Install-Package Ghostscript.NET
using Ghostscript.NET;
using Ghostscript.NET.Processor;
using System.IO;
using System.Text;

class GhostscriptExample
{
    static void Main()
    {
        // Ghostscript cannot directly convert HTML to PDF
        // You need to first convert HTML to PS/EPS using another tool
        // then use Ghostscript to convert PS to PDF
        
        string htmlContent = "<html><body><h1>Hello World</h1></body></html>";
        string psFile = "temp.ps";
        string outputPdf = "output.pdf";
        
        // This is a workaround - Ghostscript primarily works with PostScript
        GhostscriptProcessor processor = new GhostscriptProcessor();
        
        List<string> switches = new List<string>
        {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}",
            psFile
        };
        
        processor.Process(switches.ToArray());
    }
}

' NuGet: Install-Package Ghostscript.NET
Imports Ghostscript.NET
Imports Ghostscript.NET.Processor
Imports System.IO
Imports System.Text

Class GhostscriptExample
    Shared Sub Main()
        ' Ghostscript cannot directly convert HTML to PDF
        ' You need to first convert HTML to PS/EPS using another tool
        ' then use Ghostscript to convert PS to PDF

        Dim htmlContent As String = "<html><body><h1>Hello World</h1></body></html>"
        Dim psFile As String = "temp.ps"
        Dim outputPdf As String = "output.pdf"

        ' This is a workaround - Ghostscript primarily works with PostScript
        Dim processor As New GhostscriptProcessor()

        Dim switches As New List(Of String) From {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}",
            psFile
        }

        processor.Process(switches.ToArray())
    End Sub
End Class

' NuGet: Install-Package Ghostscript.NET
Imports Ghostscript.NET
Imports Ghostscript.NET.Processor
Imports System.IO
Imports System.Text

Class GhostscriptExample
    Shared Sub Main()
        ' Ghostscript cannot directly convert HTML to PDF
        ' You need to first convert HTML to PS/EPS using another tool
        ' then use Ghostscript to convert PS to PDF

        Dim htmlContent As String = "<html><body><h1>Hello World</h1></body></html>"
        Dim psFile As String = "temp.ps"
        Dim outputPdf As String = "output.pdf"

        ' This is a workaround - Ghostscript primarily works with PostScript
        Dim processor As New GhostscriptProcessor()

        Dim switches As New List(Of String) From {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}",
            psFile
        }

        processor.Process(switches.ToArray())
    End Sub
End Class

After (IronPDF):

// NuGet: Install-Package IronPdf
using IronPdf;

class IronPdfExample
{
    static void Main()
    {
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

        var renderer = new ChromePdfRenderer();

        string htmlContent = "<html><body><h1>Hello World</h1></body></html>";

        var pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("output.pdf");
    }
}

// NuGet: Install-Package IronPdf
using IronPdf;

class IronPdfExample
{
    static void Main()
    {
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

        var renderer = new ChromePdfRenderer();

        string htmlContent = "<html><body><h1>Hello World</h1></body></html>";

        var pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("output.pdf");
    }
}

Imports IronPdf

Class IronPdfExample
    Shared Sub Main()
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

        Dim renderer As New ChromePdfRenderer()

        Dim htmlContent As String = "<html><body><h1>Hello World</h1></body></html>"

        Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)
        pdf.SaveAs("output.pdf")
    End Sub
End Class

Imports IronPdf

Class IronPdfExample
    Shared Sub Main()
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

        Dim renderer As New ChromePdfRenderer()

        Dim htmlContent As String = "<html><body><h1>Hello World</h1></body></html>"

        Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)
        pdf.SaveAs("output.pdf")
    End Sub
End Class

Ghostscript cannot directly convert HTML to PDF - it expects PostScript or PDF input, so an HTML workflow requires an intermediate conversion (typically via wkhtmltopdf or similar). IronPDF's ChromePdfRenderer provides direct HTML-to-PDF rendering with CSS, JavaScript, and modern web standards support via an embedded Chromium engine. See the HTML to PDF documentation for more rendering options.

Example 2: PDF to Images

Before (Ghostscript):

// NuGet: Install-Package Ghostscript.NET
using Ghostscript.NET;
using Ghostscript.NET.Rasterizer;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;

class GhostscriptExample
{
    static void Main()
    {
        string inputPdf = "input.pdf";
        string outputPath = "output";
        
        GhostscriptVersionInfo gvi = new GhostscriptVersionInfo("gsdll64.dll");
        
        using (GhostscriptRasterizer rasterizer = new GhostscriptRasterizer())
        {
            rasterizer.Open(inputPdf, gvi, false);
            
            for (int pageNumber = 1; pageNumber <= rasterizer.PageCount; pageNumber++)
            {
                Image img = rasterizer.GetPage(300, pageNumber);
                img.Save($"{outputPath}_page{pageNumber}.png", ImageFormat.Png);
                img.Dispose();
            }
        }
    }
}

// NuGet: Install-Package Ghostscript.NET
using Ghostscript.NET;
using Ghostscript.NET.Rasterizer;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;

class GhostscriptExample
{
    static void Main()
    {
        string inputPdf = "input.pdf";
        string outputPath = "output";
        
        GhostscriptVersionInfo gvi = new GhostscriptVersionInfo("gsdll64.dll");
        
        using (GhostscriptRasterizer rasterizer = new GhostscriptRasterizer())
        {
            rasterizer.Open(inputPdf, gvi, false);
            
            for (int pageNumber = 1; pageNumber <= rasterizer.PageCount; pageNumber++)
            {
                Image img = rasterizer.GetPage(300, pageNumber);
                img.Save($"{outputPath}_page{pageNumber}.png", ImageFormat.Png);
                img.Dispose();
            }
        }
    }
}

' NuGet: Install-Package Ghostscript.NET
Imports Ghostscript.NET
Imports Ghostscript.NET.Rasterizer
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.IO

Class GhostscriptExample
    Shared Sub Main()
        Dim inputPdf As String = "input.pdf"
        Dim outputPath As String = "output"
        
        Dim gvi As New GhostscriptVersionInfo("gsdll64.dll")
        
        Using rasterizer As New GhostscriptRasterizer()
            rasterizer.Open(inputPdf, gvi, False)
            
            For pageNumber As Integer = 1 To rasterizer.PageCount
                Dim img As Image = rasterizer.GetPage(300, pageNumber)
                img.Save($"{outputPath}_page{pageNumber}.png", ImageFormat.Png)
                img.Dispose()
            Next
        End Using
    End Sub
End Class

' NuGet: Install-Package Ghostscript.NET
Imports Ghostscript.NET
Imports Ghostscript.NET.Rasterizer
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.IO

Class GhostscriptExample
    Shared Sub Main()
        Dim inputPdf As String = "input.pdf"
        Dim outputPath As String = "output"
        
        Dim gvi As New GhostscriptVersionInfo("gsdll64.dll")
        
        Using rasterizer As New GhostscriptRasterizer()
            rasterizer.Open(inputPdf, gvi, False)
            
            For pageNumber As Integer = 1 To rasterizer.PageCount
                Dim img As Image = rasterizer.GetPage(300, pageNumber)
                img.Save($"{outputPath}_page{pageNumber}.png", ImageFormat.Png)
                img.Dispose()
            Next
        End Using
    End Sub
End Class

After (IronPDF):

// NuGet: Install-Package IronPdf
using IronPdf;
using System;

class IronPdfExample
{
    static void Main()
    {
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

        var pdf = PdfDocument.FromFile("input.pdf");

        // One-shot: write every page as PNG matching Ghostscript's -r300 -sDEVICE=png16m
        pdf.RasterizeToImageFiles("output_page*.png", DPI: 300);
    }
}

// NuGet: Install-Package IronPdf
using IronPdf;
using System;

class IronPdfExample
{
    static void Main()
    {
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

        var pdf = PdfDocument.FromFile("input.pdf");

        // One-shot: write every page as PNG matching Ghostscript's -r300 -sDEVICE=png16m
        pdf.RasterizeToImageFiles("output_page*.png", DPI: 300);
    }
}

Imports IronPdf
Imports System

Class IronPdfExample
    Shared Sub Main()
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

        Dim pdf = PdfDocument.FromFile("input.pdf")

        ' One-shot: write every page as PNG matching Ghostscript's -r300 -sDEVICE=png16m
        pdf.RasterizeToImageFiles("output_page*.png", DPI:=300)
    End Sub
End Class

Imports IronPdf
Imports System

Class IronPdfExample
    Shared Sub Main()
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

        Dim pdf = PdfDocument.FromFile("input.pdf")

        ' One-shot: write every page as PNG matching Ghostscript's -r300 -sDEVICE=png16m
        pdf.RasterizeToImageFiles("output_page*.png", DPI:=300)
    End Sub
End Class

The Ghostscript approach requires locating the external gsdll64.dll, creating a GhostscriptVersionInfo object, and iterating pages with 1-indexed page numbers. IronPDF's RasterizeToImageFiles writes every page in a single call with a glob output pattern and an explicit DPI: parameter, with no external native dependency. Note that when you do work with page indices, Ghostscript uses 1-indexed pages while IronPDF uses 0-indexed pages (standard .NET convention).

Example 3: Merge PDF Files

Before (Ghostscript):

// NuGet: Install-Package Ghostscript.NET
using Ghostscript.NET;
using Ghostscript.NET.Processor;
using System.Collections.Generic;

class GhostscriptExample
{
    static void Main()
    {
        string outputPdf = "merged.pdf";
        string[] inputFiles = { "file1.pdf", "file2.pdf", "file3.pdf" };
        
        GhostscriptProcessor processor = new GhostscriptProcessor();
        
        List<string> switches = new List<string>
        {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}"
        };
        
        switches.AddRange(inputFiles);
        
        processor.Process(switches.ToArray());
    }
}

// NuGet: Install-Package Ghostscript.NET
using Ghostscript.NET;
using Ghostscript.NET.Processor;
using System.Collections.Generic;

class GhostscriptExample
{
    static void Main()
    {
        string outputPdf = "merged.pdf";
        string[] inputFiles = { "file1.pdf", "file2.pdf", "file3.pdf" };
        
        GhostscriptProcessor processor = new GhostscriptProcessor();
        
        List<string> switches = new List<string>
        {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}"
        };
        
        switches.AddRange(inputFiles);
        
        processor.Process(switches.ToArray());
    }
}

' NuGet: Install-Package Ghostscript.NET
Imports Ghostscript.NET
Imports Ghostscript.NET.Processor
Imports System.Collections.Generic

Class GhostscriptExample
    Shared Sub Main()
        Dim outputPdf As String = "merged.pdf"
        Dim inputFiles As String() = {"file1.pdf", "file2.pdf", "file3.pdf"}

        Dim processor As New GhostscriptProcessor()

        Dim switches As New List(Of String) From {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}"
        }

        switches.AddRange(inputFiles)

        processor.Process(switches.ToArray())
    End Sub
End Class

' NuGet: Install-Package Ghostscript.NET
Imports Ghostscript.NET
Imports Ghostscript.NET.Processor
Imports System.Collections.Generic

Class GhostscriptExample
    Shared Sub Main()
        Dim outputPdf As String = "merged.pdf"
        Dim inputFiles As String() = {"file1.pdf", "file2.pdf", "file3.pdf"}

        Dim processor As New GhostscriptProcessor()

        Dim switches As New List(Of String) From {
            "-dNOPAUSE",
            "-dBATCH",
            "-dSAFER",
            "-sDEVICE=pdfwrite",
            $"-sOutputFile={outputPdf}"
        }

        switches.AddRange(inputFiles)

        processor.Process(switches.ToArray())
    End Sub
End Class

After (IronPDF):

// NuGet: Install-Package IronPdf
using IronPdf;
using System.Collections.Generic;

class IronPdfExample
{
    static void Main()
    {
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

        var pdfs = new List<PdfDocument>
        {
            PdfDocument.FromFile("file1.pdf"),
            PdfDocument.FromFile("file2.pdf"),
            PdfDocument.FromFile("file3.pdf")
        };

        var merged = PdfDocument.Merge(pdfs);
        merged.SaveAs("merged.pdf");
    }
}

// NuGet: Install-Package IronPdf
using IronPdf;
using System.Collections.Generic;

class IronPdfExample
{
    static void Main()
    {
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

        var pdfs = new List<PdfDocument>
        {
            PdfDocument.FromFile("file1.pdf"),
            PdfDocument.FromFile("file2.pdf"),
            PdfDocument.FromFile("file3.pdf")
        };

        var merged = PdfDocument.Merge(pdfs);
        merged.SaveAs("merged.pdf");
    }
}

Imports IronPdf
Imports System.Collections.Generic

Class IronPdfExample
    Shared Sub Main()
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

        Dim pdfs = New List(Of PdfDocument) From {
            PdfDocument.FromFile("file1.pdf"),
            PdfDocument.FromFile("file2.pdf"),
            PdfDocument.FromFile("file3.pdf")
        }

        Dim merged = PdfDocument.Merge(pdfs)
        merged.SaveAs("merged.pdf")
    End Sub
End Class

Imports IronPdf
Imports System.Collections.Generic

Class IronPdfExample
    Shared Sub Main()
        IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

        Dim pdfs = New List(Of PdfDocument) From {
            PdfDocument.FromFile("file1.pdf"),
            PdfDocument.FromFile("file2.pdf"),
            PdfDocument.FromFile("file3.pdf")
        }

        Dim merged = PdfDocument.Merge(pdfs)
        merged.SaveAs("merged.pdf")
    End Sub
End Class

The Ghostscript approach requires the full switch incantation (-dNOPAUSE, -dBATCH, -sDEVICE=pdfwrite) and concatenating file paths into a string array. IronPDF's static Merge method takes a typed IEnumerable<PdfDocument> and returns a new PdfDocument. Learn more about merging and splitting PDFs.

Critical Migration Notes

Page Indexing Conversion

One of the most important differences in this migration is page indexing. Ghostscript switches like -dFirstPage=N / -dLastPage=M are 1-indexed; IronPDF's CopyPages is 0-indexed (standard .NET):

// Ghostscript: -dFirstPage=5 -dLastPage=8 (1-indexed, inclusive)

// IronPDF: 0-indexed page array
var extracted = pdf.CopyPages(new[] {4, 5, 6, 7});
extracted.SaveAs("pages_5_to_8.pdf");

// Ghostscript: -dFirstPage=5 -dLastPage=8 (1-indexed, inclusive)

// IronPDF: 0-indexed page array
var extracted = pdf.CopyPages(new[] {4, 5, 6, 7});
extracted.SaveAs("pages_5_to_8.pdf");

' Ghostscript: -dFirstPage=5 -dLastPage=8 (1-indexed, inclusive)

' IronPDF: 0-indexed page array
Dim extracted = pdf.CopyPages({4, 5, 6, 7})
extracted.SaveAs("pages_5_to_8.pdf")

' Ghostscript: -dFirstPage=5 -dLastPage=8 (1-indexed, inclusive)

' IronPDF: 0-indexed page array
Dim extracted = pdf.CopyPages({4, 5, 6, 7})
extracted.SaveAs("pages_5_to_8.pdf")

AGPL-3.0 License Concerns

Both Ghostscript and the Ghostscript.NET wrapper are dual-licensed under AGPL-3.0 or a commercial license from Artifex. AGPL-3.0's network-copyleft clause typically requires releasing the corresponding source of the larger work - including for SaaS / network-accessible deployments - unless you hold an Artifex commercial license. Migrating PDF workloads to IronPDF removes that obligation for the parts that move; if you keep Ghostscript only for PostScript ingest, an Artifex commercial license covers that piece. (This is a general summary, not legal advice - consult counsel for your specific deployment.)

No External Binaries

IronPDF is distributed as a NuGet package. Remove these after migration:

gsdll32.dll and gsdll64.dll files
Ghostscript installation from servers
PATH environment variable configurations
GhostscriptVersionInfo references in code

PostScript Files

IronPDF doesn't handle PostScript (.ps) files directly. If your workflow requires PostScript processing, either:

Convert PostScript to PDF using another tool before IronPDF processing
Convert source content to HTML and use IronPDF's HTML rendering

Performance Considerations

No Process Spawning

Shelling out to gswin64c.exe (or P/Invoking gsdll64.dll) carries process and native-interop overhead per operation. IronPDF runs in-process as managed .NET code:

// Ghostscript: process or P/Invoke overhead per call
processor.Process(switches.ToArray());

// IronPDF: in-process method call
var merged = PdfDocument.Merge(pdfs);

// Ghostscript: process or P/Invoke overhead per call
processor.Process(switches.ToArray());

// IronPDF: in-process method call
var merged = PdfDocument.Merge(pdfs);

' Ghostscript: process or P/Invoke overhead per call
processor.Process(switches.ToArray())

' IronPDF: in-process method call
Dim merged = PdfDocument.Merge(pdfs)

' Ghostscript: process or P/Invoke overhead per call
processor.Process(switches.ToArray())

' IronPDF: in-process method call
Dim merged = PdfDocument.Merge(pdfs)

Thread Safety

IronPDF supports concurrent use of ChromePdfRenderer and PdfDocument from multiple threads. See the IronPDF documentation for guidance on parallel rendering patterns.

Migration Checklist

Pre-Migration

Inventory all Ghostscript usage in codebase
Document current command-line switches used
Identify any PostScript processing (needs special handling)
Review AGPL-3.0 license compliance status
Obtain IronPDF license key
Create migration branch in version control

Code Migration

Remove Ghostscript.NET NuGet package: dotnet remove package Ghostscript.NET
Install IronPDF NuGet package: dotnet add package IronPdf
Remove external Ghostscript binary dependencies
Remove GhostscriptVersionInfo and DLL references
Convert GhostscriptProcessor.Process() to IronPDF methods
Convert GhostscriptRasterizer to pdf.RasterizeToImageFiles()
Replace command-line switches with API calls
Update error handling from stderr parsing to exceptions
Convert 1-indexed page numbers to 0-indexed

Testing

Test PDF to image conversion
Test PDF merging
Test page extraction
Test compression quality
Test password protection
Verify output quality matches expectations
Performance benchmark critical paths

Deployment

Remove Ghostscript from servers
Remove PATH configuration
Remove gsdll*.dll files from deployments
Verify application works without Ghostscript installed

Post-Migration

Cancel Artifex commercial license (if previously held and no longer needed)
Update documentation
Train team on IronPDF API
Monitor production for any issues

Please note: Ghostscript is a registered trademark of its respective owner. This site is not affiliated with, endorsed by, or sponsored by Artifex Software. All product names, logos, and brands are property of their respective owners. Comparisons are for informational purposes only and reflect publicly available information at the time of writing.

Curtis Chau

Chat with engineering team now

Technical Writer

Curtis Chau holds a Bachelor’s degree in Computer Science (Carleton University) and specializes in front-end development with expertise in Node.js, TypeScript, JavaScript, and React. Passionate about crafting intuitive and aesthetically pleasing user interfaces, Curtis enjoys working with modern frameworks and creating well-structured, visually appealing manuals.

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