C# PDF Library Comparison: IronPDF vs iText 7, PDFSharp, Aspose, Syncfusion, QuestPDF & More

To demonstrate IronPDF's handling of HTML content with complex CSS or JavaScript, consider the following URL conversion example:

using IronPdf;

class Program
{
    static void Main()
    {
        // Initialize the Chrome PDF renderer
        var renderer = new ChromePdfRenderer();

        // Configure rendering options for optimal output
        renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;
        renderer.RenderingOptions.EnableJavaScript = true;
        renderer.RenderingOptions.WaitFor.JavaScript(3000); // Wait 3 seconds for JS execution

        // Set page size and margins
        renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;
        renderer.RenderingOptions.MarginTop = 10; // millimeters
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.MarginLeft = 10;
        renderer.RenderingOptions.MarginRight = 10;

        // Convert URL to PDF
        var pdf = renderer.RenderUrlAsPdf("___PROTECTED_URL_170___");

        // Save the PDF document
        pdf.SaveAs("output.pdf");

        // Optional: Add metadata
        pdf.MetaData.Title = "Wikipedia Main Page";
        pdf.MetaData.Author = "IronPDF Example";
        pdf.MetaData.Subject = "URL to PDF Conversion";
    }
}

using IronPdf;

class Program
{
    static void Main()
    {
        // Initialize the Chrome PDF renderer
        var renderer = new ChromePdfRenderer();

        // Configure rendering options for optimal output
        renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;
        renderer.RenderingOptions.EnableJavaScript = true;
        renderer.RenderingOptions.WaitFor.JavaScript(3000); // Wait 3 seconds for JS execution

        // Set page size and margins
        renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;
        renderer.RenderingOptions.MarginTop = 10; // millimeters
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.MarginLeft = 10;
        renderer.RenderingOptions.MarginRight = 10;

        // Convert URL to PDF
        var pdf = renderer.RenderUrlAsPdf("___PROTECTED_URL_170___");

        // Save the PDF document
        pdf.SaveAs("output.pdf");

        // Optional: Add metadata
        pdf.MetaData.Title = "Wikipedia Main Page";
        pdf.MetaData.Author = "IronPDF Example";
        pdf.MetaData.Subject = "URL to PDF Conversion";
    }
}

What Results Can You Expect?

With minimal code, IronPDF produces high-fidelity PDFs rendering complex CSS layouts and dynamic JavaScript content. The library's Chrome rendering engine ensures pixel-perfect output matching modern browsers. Your application can immediately use this feature for handling cookies, HTTP headers, or authentication.

Verdict: IronPDF is the top choice for easy-to-use, high-performance PDF generation with excellent HTML/CSS/JS rendering and professional support. Explore demos to see it in action.

using iText.Html2pdf;
using System.Net.Http;
using System.IO;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
        var url = "___PROTECTED_URL_171___";

        // Create HTTP client with browser-like settings
        using var client = new HttpClient();

        // Add user agent to avoid 403 Forbidden responses
        client.DefaultRequestHeaders.Add("User-Agent", 
            "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 " +
            "(KHTML, like Gecko) Chrome/137.0.0.0 Safari/537.36");

        // Add timeout for reliability
        client.Timeout = TimeSpan.FromSeconds(30);

        // Fetch HTML content
        string htmlContent = await client.GetStringAsync(url);

        // Configure conversion properties
        var converterProperties = new ConverterProperties();
        converterProperties.SetBaseUri(url); // Important for resolving relative URLs

        // Create PDF from HTML
        using var fileStream = new FileStream("itext7-output.pdf", FileMode.Create);
        HtmlConverter.ConvertToPdf(htmlContent, fileStream, converterProperties);

        Console.WriteLine("PDF created successfully!");
    }
}

using iText.Html2pdf;
using System.Net.Http;
using System.IO;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
        var url = "___PROTECTED_URL_171___";

        // Create HTTP client with browser-like settings
        using var client = new HttpClient();

        // Add user agent to avoid 403 Forbidden responses
        client.DefaultRequestHeaders.Add("User-Agent", 
            "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 " +
            "(KHTML, like Gecko) Chrome/137.0.0.0 Safari/537.36");

        // Add timeout for reliability
        client.Timeout = TimeSpan.FromSeconds(30);

        // Fetch HTML content
        string htmlContent = await client.GetStringAsync(url);

        // Configure conversion properties
        var converterProperties = new ConverterProperties();
        converterProperties.SetBaseUri(url); // Important for resolving relative URLs

        // Create PDF from HTML
        using var fileStream = new FileStream("itext7-output.pdf", FileMode.Create);
        HtmlConverter.ConvertToPdf(htmlContent, fileStream, converterProperties);

        Console.WriteLine("PDF created successfully!");
    }
}

What Are the Limitations of iText 7's HTML Rendering?

This code fetches HTML content and converts it to PDF. The result preserves page layout, text, images, and CSS styles, though dynamic JavaScript content won't render. For JavaScript-heavy pages, consider IronPDF's JavaScript rendering or implement custom render delays.

Verdict: iText 7 excels at enterprise PDF generation and editing with strong compliance support and static HTML to PDF conversion. For JavaScript or advanced CSS, consider IronPDF or wkhtmltopdf.

using PdfSharp.Drawing;
using PdfSharp.Fonts;
using PdfSharp.Pdf;
using static System.Net.Mime.MediaTypeNames;

class Program
{
    static void Main()
    {
        // Configure font resolver for cross-platform compatibility
        GlobalFontSettings.UseWindowsFontsUnderWindows = true;

        // Create a new PDF document
        var document = new PdfDocument();
        document.Info.Title = "PDFSharp Example";
        document.Info.Author = "Your Team";
        document.Info.Subject = "Demonstrating PDFSharp capabilities";

        // Add a page to the document
        var page = document.AddPage();
        page.Size = PdfSharp.PageSize.A4;
        page.Orientation = PdfSharp.PageOrientation.Portrait;

        // Create graphics object for drawing
        var gfx = XGraphics.FromPdfPage(page);

        // Draw text at specific coordinates
        var font = new XFont("Verdana", 20, XFontStyleEx.Regular);
        gfx.DrawString("Hello from PDFSharp!", font, XBrushes.Black, 
            new XPoint(50, 100));

        // Add more content - a rectangle
        var pen = new XPen(XColors.Navy, 2);
        gfx.DrawRectangle(pen, XBrushes.LightBlue, 50, 150, 200, 100);

        // Add text inside rectangle
        var smallFont = new XFont("Arial", 12, XFontStyleEx.Regular);
        gfx.DrawString("Custom drawing example", smallFont, XBrushes.DarkBlue, 
            new XPoint(60, 200));

        // Save the document
        document.Save("pdfsharp-example.pdf");

        Console.WriteLine("PDF created with PDFSharp!");
    }
}

using PdfSharp.Drawing;
using PdfSharp.Fonts;
using PdfSharp.Pdf;
using static System.Net.Mime.MediaTypeNames;

class Program
{
    static void Main()
    {
        // Configure font resolver for cross-platform compatibility
        GlobalFontSettings.UseWindowsFontsUnderWindows = true;

        // Create a new PDF document
        var document = new PdfDocument();
        document.Info.Title = "PDFSharp Example";
        document.Info.Author = "Your Team";
        document.Info.Subject = "Demonstrating PDFSharp capabilities";

        // Add a page to the document
        var page = document.AddPage();
        page.Size = PdfSharp.PageSize.A4;
        page.Orientation = PdfSharp.PageOrientation.Portrait;

        // Create graphics object for drawing
        var gfx = XGraphics.FromPdfPage(page);

        // Draw text at specific coordinates
        var font = new XFont("Verdana", 20, XFontStyleEx.Regular);
        gfx.DrawString("Hello from PDFSharp!", font, XBrushes.Black, 
            new XPoint(50, 100));

        // Add more content - a rectangle
        var pen = new XPen(XColors.Navy, 2);
        gfx.DrawRectangle(pen, XBrushes.LightBlue, 50, 150, 200, 100);

        // Add text inside rectangle
        var smallFont = new XFont("Arial", 12, XFontStyleEx.Regular);
        gfx.DrawString("Custom drawing example", smallFont, XBrushes.DarkBlue, 
            new XPoint(60, 200));

        // Save the document
        document.Save("pdfsharp-example.pdf");

        Console.WriteLine("PDF created with PDFSharp!");
    }
}

When Is PDFSharp the Right Choice?

This code generates PDFs programmatically, adding text and handling layout manually. The implementation provides clear benefits for customized documents without HTML input like invoices, forms, or certificates. For similar programmatic control with more features, see creating new PDFs.

Verdict: PDFSharp & MigraDoc are ideal for basic PDF creation—free and easy to integrate but lack HTML conversion and advanced editing. For HTML workflows, consider IronPDF's HTML to PDF capabilities.## What Is Aspose.PDF and When Should You Use It?

Aspose.PDF is a commercial .NET PDF library offering complete tools for creating, editing, converting, and securing PDFs. Unlike lightweight libraries, Aspose.PDF focuses on enterprise applications, supporting file conversions including Word, Excel, HTML, and XML. Your application can immediately use this feature for document automation, report generation, and advanced PDF manipulation in large-scale applications. See our Aspose vs IronPDF comparison.

using Syncfusion.HtmlConverter;
using Syncfusion.Pdf;

class Program
{
    static void Main()
    {
        // Initialize the HTML to PDF converter
        HtmlToPdfConverter converter = new HtmlToPdfConverter();

        // Configure WebKit settings for better rendering
        WebKitConverterSettings settings = new WebKitConverterSettings();

        // Set WebKit path (required for deployment)
        settings.WebKitPath = @"C:\QtBinariesPath";

        // Configure page settings
        settings.PdfPageSize = PdfPageSize.A4;
        settings.Orientation = PdfPageOrientation.Portrait;
        settings.Margin = new PdfMargins() { All = 20 };

        // Enable JavaScript execution
        settings.EnableJavaScript = true;
        settings.JavaScriptDelay = 3000; // Wait 3 seconds for JS

        // Set viewport size for responsive design
        settings.ViewPortSize = new System.Drawing.Size(1024, 0);

        // Add custom headers if needed
        settings.HttpRequestHeaders.Add("User-Agent", 
            "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36");

        converter.ConverterSettings = settings;

        // Convert URL to PDF
        PdfDocument document = converter.Convert("___PROTECTED_URL_173___");

        // Add document info
        document.DocumentInformation.Title = "Wikipedia Main Page";
        document.DocumentInformation.Author = "Syncfusion Example";
        document.DocumentInformation.Subject = "URL to PDF Conversion";

        // Save the PDF
        document.Save("syncfusion-output.pdf");
        document.Close(true); // true = dispose resources

        Console.WriteLine("PDF created successfully!");
    }
}

using Syncfusion.HtmlConverter;
using Syncfusion.Pdf;

class Program
{
    static void Main()
    {
        // Initialize the HTML to PDF converter
        HtmlToPdfConverter converter = new HtmlToPdfConverter();

        // Configure WebKit settings for better rendering
        WebKitConverterSettings settings = new WebKitConverterSettings();

        // Set WebKit path (required for deployment)
        settings.WebKitPath = @"C:\QtBinariesPath";

        // Configure page settings
        settings.PdfPageSize = PdfPageSize.A4;
        settings.Orientation = PdfPageOrientation.Portrait;
        settings.Margin = new PdfMargins() { All = 20 };

        // Enable JavaScript execution
        settings.EnableJavaScript = true;
        settings.JavaScriptDelay = 3000; // Wait 3 seconds for JS

        // Set viewport size for responsive design
        settings.ViewPortSize = new System.Drawing.Size(1024, 0);

        // Add custom headers if needed
        settings.HttpRequestHeaders.Add("User-Agent", 
            "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36");

        converter.ConverterSettings = settings;

        // Convert URL to PDF
        PdfDocument document = converter.Convert("___PROTECTED_URL_173___");

        // Add document info
        document.DocumentInformation.Title = "Wikipedia Main Page";
        document.DocumentInformation.Author = "Syncfusion Example";
        document.DocumentInformation.Subject = "URL to PDF Conversion";

        // Save the PDF
        document.Save("syncfusion-output.pdf");
        document.Close(true); // true = dispose resources

        Console.WriteLine("PDF created successfully!");
    }
}

What Are Syncfusion's Reporting Strengths?

This example converts URLs to PDFs, preserving layout, images, and formatting. Syncfusion PDF excels in reporting scenarios requiring reliable HTML to PDF rendering. The library supports headers and footers, page numbers, and bookmarks for professional documents.

Verdict: Syncfusion PDF is excellent for teams using Syncfusion components, needing professional HTML to PDF rendering, or wanting enterprise PDF generation with broad features. For alternatives, explore our detailed comparison.

using QuestPDF.Fluent;
using QuestPDF.Helpers;
using QuestPDF.Infrastructure;
using QuestPDF.Previewer;

class Program
{
    static void Main()
    {
        // Configure license (Community, Professional, or Enterprise)
        QuestPDF.Settings.License = LicenseType.Community;

        // Create document with fluent API
        Document.Create(container =>
        {
            container.Page(page =>
            {
                // Page settings
                page.Size(PageSizes.A4);
                page.Margin(2, Unit.Centimetre);
                page.PageColor(Colors.White);
                page.DefaultTextStyle(x => x.FontSize(12).FontFamily(Fonts.Arial));

                // Header section
                page.Header()
                    .Height(100)
                    .Background(Colors.Grey.Lighten3)
                    .AlignCenter()
                    .AlignMiddle()
                    .Text("QuestPDF Example Document")
                    .FontSize(20)
                    .Bold()
                    .FontColor(Colors.Blue.Darken2);

                // Content section
                page.Content()
                    .PaddingVertical(1, Unit.Centimetre)
                    .Column(column =>
                    {
                        column.Spacing(20);

                        // Add title
                        column.Item().Text("Hello from QuestPDF!")
                            .FontSize(16)
                            .SemiBold()
                            .FontColor(Colors.Blue.Medium);

                        // Add paragraph
                        column.Item().Text(text =>
                        {
                            text.Span("This is an example of programmatic PDF generation using ");
                            text.Span("QuestPDF").Bold();
                            text.Span(". You have complete control over layout and styling.");
                        });

                        // Add table
                        column.Item().Table(table =>
                        {
                            table.ColumnsDefinition(columns =>
                            {
                                columns.RelativeColumn();
                                columns.RelativeColumn();
                            });

                            // Table header
                            table.Header(header =>
                            {
                                header.Cell().Background(Colors.Grey.Medium)
                                    .Padding(5).Text("Feature").Bold();
                                header.Cell().Background(Colors.Grey.Medium)
                                    .Padding(5).Text("Description").Bold();
                            });

                            // Table rows
                            table.Cell().Border(1).Padding(5).Text("Fluent API");
                            table.Cell().Border(1).Padding(5)
                                .Text("Build documents using method chaining");

                            table.Cell().Border(1).Padding(5).Text("Layout Control");
                            table.Cell().Border(1).Padding(5)
                                .Text("Precise control over element positioning");
                        });
                    });

                // Footer section
                page.Footer()
                    .Height(50)
                    .AlignCenter()
                    .Text(text =>
                    {
                        text.Span("Page ");
                        text.CurrentPageNumber();
                        text.Span(" of ");
                        text.TotalPages();
                    });
            });
        })
        .GeneratePdf("questpdf-output.pdf");

        Console.WriteLine("PDF created with QuestPDF!");
    }
}

using QuestPDF.Fluent;
using QuestPDF.Helpers;
using QuestPDF.Infrastructure;
using QuestPDF.Previewer;

class Program
{
    static void Main()
    {
        // Configure license (Community, Professional, or Enterprise)
        QuestPDF.Settings.License = LicenseType.Community;

        // Create document with fluent API
        Document.Create(container =>
        {
            container.Page(page =>
            {
                // Page settings
                page.Size(PageSizes.A4);
                page.Margin(2, Unit.Centimetre);
                page.PageColor(Colors.White);
                page.DefaultTextStyle(x => x.FontSize(12).FontFamily(Fonts.Arial));

                // Header section
                page.Header()
                    .Height(100)
                    .Background(Colors.Grey.Lighten3)
                    .AlignCenter()
                    .AlignMiddle()
                    .Text("QuestPDF Example Document")
                    .FontSize(20)
                    .Bold()
                    .FontColor(Colors.Blue.Darken2);

                // Content section
                page.Content()
                    .PaddingVertical(1, Unit.Centimetre)
                    .Column(column =>
                    {
                        column.Spacing(20);

                        // Add title
                        column.Item().Text("Hello from QuestPDF!")
                            .FontSize(16)
                            .SemiBold()
                            .FontColor(Colors.Blue.Medium);

                        // Add paragraph
                        column.Item().Text(text =>
                        {
                            text.Span("This is an example of programmatic PDF generation using ");
                            text.Span("QuestPDF").Bold();
                            text.Span(". You have complete control over layout and styling.");
                        });

                        // Add table
                        column.Item().Table(table =>
                        {
                            table.ColumnsDefinition(columns =>
                            {
                                columns.RelativeColumn();
                                columns.RelativeColumn();
                            });

                            // Table header
                            table.Header(header =>
                            {
                                header.Cell().Background(Colors.Grey.Medium)
                                    .Padding(5).Text("Feature").Bold();
                                header.Cell().Background(Colors.Grey.Medium)
                                    .Padding(5).Text("Description").Bold();
                            });

                            // Table rows
                            table.Cell().Border(1).Padding(5).Text("Fluent API");
                            table.Cell().Border(1).Padding(5)
                                .Text("Build documents using method chaining");

                            table.Cell().Border(1).Padding(5).Text("Layout Control");
                            table.Cell().Border(1).Padding(5)
                                .Text("Precise control over element positioning");
                        });
                    });

                // Footer section
                page.Footer()
                    .Height(50)
                    .AlignCenter()
                    .Text(text =>
                    {
                        text.Span("Page ");
                        text.CurrentPageNumber();
                        text.Span(" of ");
                        text.TotalPages();
                    });
            });
        })
        .GeneratePdf("questpdf-output.pdf");

        Console.WriteLine("PDF created with QuestPDF!");
    }
}

When Does QuestPDF Excel?

This demonstrates programmatic PDF creation with full control over content and layout without HTML input. QuestPDF excels at creating invoices, forms, and structured reports requiring precise positioning. For teams needing similar control with HTML support, explore IronPDF's programmatic features.

Verdict: QuestPDF is perfect for developers needing full programmatic control over PDF content. While lacking HTML conversion, it excels at structured, dynamically generated PDFs for reporting and automation.