Converting HTML to PDF in C# Using .NET 10
IronPDF enables C# developers to convert HTML to PDF using a Chrome-based rendering engine, supporting CSS, JavaScript, and dynamic content generation in just a few lines of code for .NET 10 applications.
Converting HTML to PDF in C# is a common requirement for .NET developers building enterprise applications. Whether you're generating PDF files from web content, HTML documents, or HTML strings, the ability to convert HTML into professional PDFs is essential for creating reports, invoices, and other printable assets.
The IronPDF library is a powerful HTML to PDF converter built for .NET Framework applications and modern .NET 10 projects. It lets you easily convert HTML, CSS styles, and even JavaScript rendering into high-quality PDF documents — all in just a few lines of C# code. The library leverages a Chrome rendering engine that ensures pixel-perfect conversion.

Why Should I Use IronPDF for HTML to PDF Conversion?
Unlike older PDF libraries requiring manual element drawing, IronPDF renders HTML content using a full Chromium engine. This means your HTML file, CSS, and image files are processed exactly as a browser would, preserving layout, fonts, and HTML elements precisely. It's ideal for:
- Generating dynamic reports with custom margins
- Rendering web pages or dashboards as PDFs
- Converting HTML into PDFs with headers and footers
- Automating PDF generation using async processing
- Manipulating existing PDFs for stamping or merging
IronPDF acts as a full converter library to create PDF documents, giving .NET developers both simplicity and powerful control over PDF generation. The library supports UTF-8 encoding for international languages and provides comprehensive rendering options for customization.
How Do I Install IronPDF in a .NET 10 Project?
First, create a new .NET 10 project. For detailed installation guidance, refer to the IronPDF installation overview or NuGet package documentation.

Currently, .NET 10 is in preview, but it's fully compatible with IronPDF. The library maintains compatibility across platforms including Windows, Linux, and macOS.

We'll use it here to demonstrate how HTML-to-PDF conversion works seamlessly with the latest .NET features and IronPDF's Chrome-based rendering engine.
Now let's install IronPDF!
You can install IronPDF directly from NuGet Package Manager for Solutions.

There are other installation options too. In your Solution Explorer, open the terminal or Command Line Interface (CLI) and run:
dotnet add package IronPdfdotnet add package IronPdfor using NuGet Package Manager Console:
PM > Install-Package IronPdf
Now you're ready to start coding. For proper configuration, ensure you've applied your license key if using the commercial version.
How Do I Perform Basic HTML to PDF Conversion?
Let's start with a C# HTML to PDF example that converts HTML content into a PDF file. This basic approach works well for simple documents and demonstrates the core API.
using IronPdf;
class Program
{
public static void Main()
{
var renderer = new ChromePdfRenderer();
string html = "<html><body><h1>HTML to PDF C# Example</h1><p>This demonstrates PDF conversion in .NET 10.</p></body></html>";
PdfDocument pdf = renderer.RenderHtmlAsPdf(html);
pdf.SaveAs("basic_output.pdf");
}
}using IronPdf;
class Program
{
public static void Main()
{
var renderer = new ChromePdfRenderer();
string html = "<html><body><h1>HTML to PDF C# Example</h1><p>This demonstrates PDF conversion in .NET 10.</p></body></html>";
PdfDocument pdf = renderer.RenderHtmlAsPdf(html);
pdf.SaveAs("basic_output.pdf");
}
}Explanation:
ChromePdfRendereris the main converter class using ChromiumRenderHtmlAsPdfconverts HTML strings to PdfDocument objects- The PDF can be saved to file or returned as stream
In just a few lines, we've built a working HTML to PDF converter using C#.

How Do I Convert HTML Files and URLs to PDF?
When Should I Convert Local HTML Files?
You can convert HTML files from disk, including linked resources like CSS or images. This is useful when working with templates or managing fonts and Base URLs:
var renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderHtmlFileAsPdf("template.html");
pdf.SaveAs("file_conversion.pdf");var renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderHtmlFileAsPdf("template.html");
pdf.SaveAs("file_conversion.pdf");This method reads your local HTML file and automatically loads external resources. For complex scenarios, you can convert HTML ZIP files containing all assets.

When Should I Convert Web Pages Using URL?
If your input is a web page or existing URL, render it directly. This approach captures live web content, dashboards, or handles cookies and HTTP request headers:
var renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderUrlAsPdf("___PROTECTED_URL_96___");
pdf.SaveAs("webpage_conversion.pdf");var renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderUrlAsPdf("___PROTECTED_URL_96___");
pdf.SaveAs("webpage_conversion.pdf");The code performs URL-to-PDF conversion, rendering the HTML document with full JavaScript and CSS support. For authenticated pages, configure TLS website logins.

How Do I Convert HTML Content with Styling and JavaScript?
Many web pages use dynamic elements, CSS styles, and JavaScript rendering (charts, dashboards). IronPDF fully supports this through its WaitFor API:
var renderer = new ChromePdfRenderer();
renderer.RenderingOptions.EnableJavaScript = true;
renderer.RenderingOptions.WaitFor.RenderDelay(2000); // wait for dynamic JS
renderer.RenderingOptions.MarginTop = 20;
renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;
// Custom paper size is also available
renderer.RenderingOptions.SetCustomPaperSize(210, 297); // A4 in mm
PdfDocument pdf = renderer.RenderHtmlFileAsPdf("Reports/sales.html");
pdf.SaveAs("styled_output.pdf");var renderer = new ChromePdfRenderer();
renderer.RenderingOptions.EnableJavaScript = true;
renderer.RenderingOptions.WaitFor.RenderDelay(2000); // wait for dynamic JS
renderer.RenderingOptions.MarginTop = 20;
renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;
// Custom paper size is also available
renderer.RenderingOptions.SetCustomPaperSize(210, 297); // A4 in mm
PdfDocument pdf = renderer.RenderHtmlFileAsPdf("Reports/sales.html");
pdf.SaveAs("styled_output.pdf");This ensures IronPDF waits for dynamic content to load before rendering, resulting in accurate visual output. You can also render WebGL sites and handle complex web fonts.

How Do I Add Headers, Footers & Page Numbers?
Add professional headers and footers to your PDFs easily. IronPDF supports both text headers and rich HTML headers with page numbers:
renderer.RenderingOptions.FirstPageNumber = 1;
renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter()
{
HtmlFragment = "<div style='text-align:center; font-size:14px; margin-top:20px;'>Sales Report</div>",
Height = 30,
Spacing = 5
};
renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter()
{
HtmlFragment = "<div style='text-align:center; font-size:14px; margin-bottom:20px;'>Page {page} of {total-pages}</div>",
Height = 30,
Spacing = 5
};renderer.RenderingOptions.FirstPageNumber = 1;
renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter()
{
HtmlFragment = "<div style='text-align:center; font-size:14px; margin-top:20px;'>Sales Report</div>",
Height = 30,
Spacing = 5
};
renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter()
{
HtmlFragment = "<div style='text-align:center; font-size:14px; margin-bottom:20px;'>Page {page} of {total-pages}</div>",
Height = 30,
Spacing = 5
};IronPDF treats these as HTML elements, so you can style them with CSS and include custom data like dates or company names. For simpler needs, use text headers and footers.

How Do I Generate PDFs from Multiple HTML Snippets?
To generate PDFs by combining HTML snippets, you can merge them. This creates multi-section reports or combines content from different sources:
var renderer = new ChromePdfRenderer();
PdfDocument part1 = renderer.RenderHtmlAsPdf("<h1>Section 1</h1><p>First section content</p>");
PdfDocument part2 = renderer.RenderHtmlAsPdf("<h1>Section 2</h1><p>Second section content</p>");
var merged = PdfDocument.Merge(part1, part2);
merged.SaveAs("Merged.pdf");
// Alternative approach: copy specific pages
var combinedDoc = new PdfDocument();
combinedDoc.CopyPage(part1, 0); // Copy first page
combinedDoc.CopyPage(part2, 0); // Copy first page
combinedDoc.SaveAs("Combined.pdf");var renderer = new ChromePdfRenderer();
PdfDocument part1 = renderer.RenderHtmlAsPdf("<h1>Section 1</h1><p>First section content</p>");
PdfDocument part2 = renderer.RenderHtmlAsPdf("<h1>Section 2</h1><p>Second section content</p>");
var merged = PdfDocument.Merge(part1, part2);
merged.SaveAs("Merged.pdf");
// Alternative approach: copy specific pages
var combinedDoc = new PdfDocument();
combinedDoc.CopyPage(part1, 0); // Copy first page
combinedDoc.CopyPage(part2, 0); // Copy first page
combinedDoc.SaveAs("Combined.pdf");This helps when creating multi-section reports from different HTML fragments. You can also add bookmarks to improve navigation.

How Do I Convert HTML to PDF in Web APIs?
In ASP.NET Web API, generate and return PDFs without saving to disk using MemoryStream. This pattern is ideal for Blazor applications and RESTful services:
[HttpGet("download")]
public IActionResult GetPdf()
{
var renderer = new ChromePdfRenderer();
string html = "<h1>Web Report</h1><p>Generated dynamically.</p>";
var pdf = renderer.RenderHtmlAsPdf(html);
var bytes = pdf.BinaryData;
// Optional: Add metadata
pdf.MetaData.Author = "API Service";
pdf.MetaData.CreationDate = DateTime.Now;
return File(bytes, "application/pdf", "report.pdf");
}[HttpGet("download")]
public IActionResult GetPdf()
{
var renderer = new ChromePdfRenderer();
string html = "<h1>Web Report</h1><p>Generated dynamically.</p>";
var pdf = renderer.RenderHtmlAsPdf(html);
var bytes = pdf.BinaryData;
// Optional: Add metadata
pdf.MetaData.Author = "API Service";
pdf.MetaData.CreationDate = DateTime.Now;
return File(bytes, "application/pdf", "report.pdf");
}This pattern works great for server-side PDF generation in .NET 10 web applications. You can integrate with CSHTML views for MVC applications.
How Do I Customize HTML Rendering Options?
Control how HTML elements and resources render with comprehensive rendering options:
renderer.RenderingOptions.BaseUrl = "___PROTECTED_URL_97___";
renderer.RenderingOptions.CustomHeaders.Add("Authorization", "Bearer token");
renderer.RenderingOptions.WaitFor.NavigationTimeout = 10000;
renderer.RenderingOptions.EnableJavaScript = true;
// Configure paper and margins
renderer.RenderingOptions.PaperOrientation = PdfPaperOrientation.Landscape;
renderer.RenderingOptions.MarginBottom = 25;
renderer.RenderingOptions.MarginTop = 25;
renderer.RenderingOptions.MarginLeft = 20;
renderer.RenderingOptions.MarginRight = 20;
// Set viewport for responsive design
renderer.RenderingOptions.ViewPortWidth = 1920;
renderer.RenderingOptions.ViewPortHeight = 1080;renderer.RenderingOptions.BaseUrl = "___PROTECTED_URL_97___";
renderer.RenderingOptions.CustomHeaders.Add("Authorization", "Bearer token");
renderer.RenderingOptions.WaitFor.NavigationTimeout = 10000;
renderer.RenderingOptions.EnableJavaScript = true;
// Configure paper and margins
renderer.RenderingOptions.PaperOrientation = PdfPaperOrientation.Landscape;
renderer.RenderingOptions.MarginBottom = 25;
renderer.RenderingOptions.MarginTop = 25;
renderer.RenderingOptions.MarginLeft = 20;
renderer.RenderingOptions.MarginRight = 20;
// Set viewport for responsive design
renderer.RenderingOptions.ViewPortWidth = 1920;
renderer.RenderingOptions.ViewPortHeight = 1080;This helps when rendering pages with external resources or performing web scraping followed by PDF conversion. For print optimization, configure CSS media types and custom paper sizes.
How Do I Create Command Line Tools for PDF Conversion?
Build command line tools for batch HTML to PDF conversion, useful for automation and CI/CD pipelines:
using IronPdf;
using System;
class Program
{
public static void Main(string[] args)
{
if (args.Length < 2)
{
Console.WriteLine("Usage: pdfconvert input.html output.pdf");
return;
}
string inputFile = args[0];
string outputPath = args[1];
var renderer = new ChromePdfRenderer();
// Configure compression for smaller files
renderer.RenderingOptions.CompressImages = true;
PdfDocument pdf = renderer.RenderHtmlFileAsPdf(inputFile);
pdf.SaveAs(outputPath);
Console.WriteLine("PDF generated successfully!");
}
}using IronPdf;
using System;
class Program
{
public static void Main(string[] args)
{
if (args.Length < 2)
{
Console.WriteLine("Usage: pdfconvert input.html output.pdf");
return;
}
string inputFile = args[0];
string outputPath = args[1];
var renderer = new ChromePdfRenderer();
// Configure compression for smaller files
renderer.RenderingOptions.CompressImages = true;
PdfDocument pdf = renderer.RenderHtmlFileAsPdf(inputFile);
pdf.SaveAs(outputPath);
Console.WriteLine("PDF generated successfully!");
}
}Run it from the Command Line Interface (CLI):
dotnet run "input.html" "output.pdf"
You've built a simple command line PDF converter for .NET developers. For production use, add custom logging and error handling.

How Do I Use Async Patterns for PDF Generation?
Use async patterns for modern .NET 10 applications. This approach is essential for multithreaded generation in high-performance scenarios:
public static async Task Main()
{
var renderer = new ChromePdfRenderer();
string url = "___PROTECTED_URL_98___";
// Async rendering with cancellation token support
using var cts = new CancellationTokenSource(TimeSpan.FromMinutes(2));
PdfDocument pdf = await renderer.RenderUrlAsPdfAsync(url, cts.Token);
pdf.SaveAs("async_output.pdf");
// For parallel processing of multiple documents
var urls = new[] { "___PROTECTED_URL_99___", "___PROTECTED_URL_100___", "___PROTECTED_URL_101___" };
var tasks = urls.Select(u => renderer.RenderUrlAsPdfAsync(u)).ToArray();
var pdfs = await Task.WhenAll(tasks);
// Merge all PDFs
var combined = PdfDocument.Merge(pdfs);
combined.SaveAs("batch_output.pdf");
}public static async Task Main()
{
var renderer = new ChromePdfRenderer();
string url = "___PROTECTED_URL_98___";
// Async rendering with cancellation token support
using var cts = new CancellationTokenSource(TimeSpan.FromMinutes(2));
PdfDocument pdf = await renderer.RenderUrlAsPdfAsync(url, cts.Token);
pdf.SaveAs("async_output.pdf");
// For parallel processing of multiple documents
var urls = new[] { "___PROTECTED_URL_99___", "___PROTECTED_URL_100___", "___PROTECTED_URL_101___" };
var tasks = urls.Select(u => renderer.RenderUrlAsPdfAsync(u)).ToArray();
var pdfs = await Task.WhenAll(tasks);
// Merge all PDFs
var combined = PdfDocument.Merge(pdfs);
combined.SaveAs("batch_output.pdf");
}This works great for scalable systems or cloud APIs handling high-volume PDF generation. For better performance, consider parallel PDF generation.
What Are the Best Practices for Large-Scale PDF Generation?
- Reuse
ChromePdfRendererinstances to reduce overhead - Store temporary files on fast SSD storage or use memory streams
- Use async tasks with proper cancellation token support
- Avoid excessive JavaScript rendering by configuring render delays
- Validate HTML input to prevent conversion errors
- Implement PDF compression for smaller files
- Consider linearizing PDFs for web viewing
For deployment, IronPDF supports Azure, AWS Lambda, and Docker containers. The library provides extensive performance optimization guidance.
Advanced Features for Enterprise Applications
IronPDF offers advanced features for enterprise scenarios:
- Digital signatures for authentication
- PDF/A compliance for archival
- PDF/UA support for accessibility
- Form creation and editing
- Watermarking and stamping
- Text extraction and replacement
- PDF encryption and security
Conclusion
With IronPDF and .NET 10, converting HTML content into professional PDFs is straightforward — whether you're working with HTML strings, local files, or URLs. The library's Chrome-based rendering engine ensures perfect fidelity with modern web standards including CSS3 and JavaScript.
From simple snippets to large-scale generation, IronPDF provides a complete HTML to PDF converter with support for JavaScript, CSS, custom headers, and linked resources. The comprehensive API handles everything from basic conversions to complex enterprise requirements like digital signatures and PDF organization.
In just a few lines of code, you can generate PDFs, automate report generation, or embed a PDF converter directly into your .NET applications. The library's extensive documentation and code examples make getting started easy.
Start experimenting with HTML-to-PDF projects today using the IronPDF free trial. Download Now and experience how effortlessly you can generate high-quality PDFs from your HTML content. For detailed comparisons with alternatives, check out how IronPDF compares to iText, Aspose, and other PDF libraries.
Frequently Asked Questions
What is the primary use of converting HTML to PDF in C#?
The primary use of converting HTML to PDF in C# is to generate professional PDF files from web content, HTML documents, or HTML strings. This is essential for creating reports, invoices, and other printable assets in enterprise or SaaS applications.
Why is HTML to PDF conversion important for .NET developers?
HTML to PDF conversion is important for .NET developers because it enables them to integrate document generation functionalities into their applications, which is crucial for producing high-quality, shareable, and printable documents like reports and invoices.
Can IronPDF handle large HTML documents for conversion to PDF?
Yes, IronPDF can efficiently handle large HTML documents and convert them into PDFs without compromising on performance or quality.
Does IronPDF support the conversion of HTML strings to PDF?
IronPDF supports converting HTML strings to PDF, allowing developers to dynamically generate PDF documents directly from HTML content.
What type of applications benefit from using IronPDF for HTML to PDF conversion?
Enterprise and SaaS applications benefit greatly from using IronPDF for HTML to PDF conversion, as it enables them to automate the creation of professional documents like reports and invoices.
How does IronPDF ensure high-quality PDF output from HTML?
IronPDF ensures high-quality PDF output by using advanced rendering techniques that accurately convert HTML, CSS, and JavaScript into professional-looking PDFs.
Is it possible to customize the appearance of PDFs generated from HTML using IronPDF?
Yes, IronPDF allows extensive customization of the appearance of PDFs generated from HTML, including layout, fonts, and styles, to match specific design requirements.
Can IronPDF convert web pages directly to PDF?
IronPDF can convert web pages directly to PDF, enabling developers to transform live web content into static, shareable PDF documents easily.
Does IronPDF support the integration of graphics and images in PDF documents?
IronPDF supports the integration of graphics and images, ensuring that the converted PDF documents maintain the visual elements of the original HTML content.









