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Comparing C# HTML to PDF Open Source vs. IronPDF

Published:November 13, 2025

Converting HTML to PDF is a fundamental requirement in modern .NET projects. Whether you're generating reports, invoices, or archiving entire web pages, choosing the right .NET library can significantly impact your development process. This article compares popular HTML to PDF C# open-source solutions with IronPDF, helping you make an informed decision for your large-scale PDF generation needs.

What Open Source HTML to PDF Options Exist for C#?

The .NET ecosystem offers several open-source libraries for HTML to PDF conversion. Each comes with its own strengths and limitations that developers should carefully consider. These often handle different file formats and vary in CSS support.

PuppeteerSharp - The Chromium-Based Solution

Open Source HTML to PDF Converters vs IronPDF: Image 1

PuppeteerSharp stands out as the most popular open-source option for converting HTML code to PDF format in C#. As a .NET port of Google's Puppeteer, it uses a headless Chromium browser to render web content with full support for modern web technologies. The conversion process involves an HTML document being rendered by a powerful PDF engine.

Code Example: Convert Simple HTML String to PDF File

using PuppeteerSharp;
using System.Threading.Tasks;

class Program
{
    static async Task Main(string[] args)
    {
        // Download Chromium browser
        var browserFetcher = new BrowserFetcher();
        await browserFetcher.DownloadAsync();
        // Launch browser and convert HTML string
        using var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true });
        using var page = await browser.NewPageAsync();
        // HTML content with CSS styling and JavaScript
        var html = @"
            <html>
            <head>
                <style>
                    body { font-family: Arial, sans-serif; }
                    .header { color: #2563eb; font-size: 24px; }
                    .content { margin: 20px; }
                </style>
            </head>
            <body>
                <div class='header'>Invoice #12345</div>
                <div class='content'>
                    <p>Generated on: <span id='date'></span></p>
                    <script>
                        document.getElementById('date').innerText = new Date().toLocaleDateString();
                    </script>
                </div>
            </body>
            </html>";
        await page.SetContentAsync(html);
        await page.PdfAsync("output.pdf", new PdfOptions 
        { 
            Format = PaperFormat.A4,
            PrintBackground = true 
        });
    }
}

using PuppeteerSharp;
using System.Threading.Tasks;

class Program
{
    static async Task Main(string[] args)
    {
        // Download Chromium browser
        var browserFetcher = new BrowserFetcher();
        await browserFetcher.DownloadAsync();
        // Launch browser and convert HTML string
        using var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true });
        using var page = await browser.NewPageAsync();
        // HTML content with CSS styling and JavaScript
        var html = @"
            <html>
            <head>
                <style>
                    body { font-family: Arial, sans-serif; }
                    .header { color: #2563eb; font-size: 24px; }
                    .content { margin: 20px; }
                </style>
            </head>
            <body>
                <div class='header'>Invoice #12345</div>
                <div class='content'>
                    <p>Generated on: <span id='date'></span></p>
                    <script>
                        document.getElementById('date').innerText = new Date().toLocaleDateString();
                    </script>
                </div>
            </body>
            </html>";
        await page.SetContentAsync(html);
        await page.PdfAsync("output.pdf", new PdfOptions 
        { 
            Format = PaperFormat.A4,
            PrintBackground = true 
        });
    }
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

PuppeteerSharp excels at rendering web pages with complex templates and JavaScript execution. However, it requires downloading and managing a Chromium instance (approximately 150MB), which can complicate deployment and increase resource consumption. You are essentially using a heavy-duty PDF converter.

Other Open Source Alternatives

Comparing C# HTML to PDF Open Source vs. IronPDF: Figure 3

wkhtmltopdf was once a popular choice but comes with significant drawbacks. This command-line tool hasn't been actively maintained since 2020 and has known security vulnerabilities that will never be patched. While it can handle basic HTML to PDF conversions, it struggles with modern CSS3 and JavaScript rendering.

PdfSharp/HtmlRenderer.PdfSharp provides a lightweight solution but lacks native HTML conversion capabilities. It requires manual HTML parsing and positioning, making it suitable only for simple HTML snippets without complex styling or JavaScript support. Compared to other libraries, this requires significant manual work to create PDF documents.

How Does IronPDF Simplify PDF Generation?

Comparing C# HTML to PDF Open Source vs. IronPDF: Figure 3

IronPDF offers a comprehensive approach to HTML to PDF conversion with its built-in Chrome rendering engine. Unlike open-source alternatives, it provides a streamlined, intuitive API that handles complex HTML elements without requiring external dependencies. Developers can easily use IronPDF in Visual Studio across various .NET versions. You can also convert documents from Microsoft Office formats.

Code Example: Convert HTML to PDF

using IronPdf;

class Program
{
    static void Main(string[] args)
    {
        // Initialize renderer
        var renderer = new ChromePdfRenderer();
        // Configure rendering options
        renderer.RenderingOptions.MarginTop = 10;
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.EnableJavaScript = true;
        // HTML with advanced CSS and JavaScript
        var html = @"
            <html>
            <head>
                <style>
                    body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; }
                    .invoice-header { 
                        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
                        color: white;
                        padding: 20px;
                        border-radius: 8px;
                    }
                    table { width: 100%; border-collapse: collapse; }
                    th, td { padding: 10px; border-bottom: 1px solid #ddd; }
                </style>
            </head>
            <body>
                <div class='invoice-header'>
                    <h1>Professional Invoice</h1>
                </div>
                <table>
                    <tr><th>Item</th><th>Price</th></tr>
                    <tr><td>Service A</td><td>$100</td></tr>
                </table>
                <script>
                    console.log('PDF generated with IronPDF');
                </script>
            </body>
            </html>";
        // Generate PDF with just a few lines
        var pdf = renderer.RenderHtmlAsPdf(html);
        pdf.SaveAs("professional-invoice.pdf");
        // Can also convert HTML files or URLs
        var urlPdf = renderer.RenderUrlAsPdf("https://example.com");
        var filePdf = renderer.RenderHtmlFileAsPdf("template.html");
    }
}

using IronPdf;

class Program
{
    static void Main(string[] args)
    {
        // Initialize renderer
        var renderer = new ChromePdfRenderer();
        // Configure rendering options
        renderer.RenderingOptions.MarginTop = 10;
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.EnableJavaScript = true;
        // HTML with advanced CSS and JavaScript
        var html = @"
            <html>
            <head>
                <style>
                    body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; }
                    .invoice-header { 
                        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
                        color: white;
                        padding: 20px;
                        border-radius: 8px;
                    }
                    table { width: 100%; border-collapse: collapse; }
                    th, td { padding: 10px; border-bottom: 1px solid #ddd; }
                </style>
            </head>
            <body>
                <div class='invoice-header'>
                    <h1>Professional Invoice</h1>
                </div>
                <table>
                    <tr><th>Item</th><th>Price</th></tr>
                    <tr><td>Service A</td><td>$100</td></tr>
                </table>
                <script>
                    console.log('PDF generated with IronPDF');
                </script>
            </body>
            </html>";
        // Generate PDF with just a few lines
        var pdf = renderer.RenderHtmlAsPdf(html);
        pdf.SaveAs("professional-invoice.pdf");
        // Can also convert HTML files or URLs
        var urlPdf = renderer.RenderUrlAsPdf("https://example.com");
        var filePdf = renderer.RenderHtmlFileAsPdf("template.html");
    }
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

IronPDF's API key-driven design makes HTML to PDF conversion remarkably straightforward. The library handles all the complexities of PDF generation internally, from managing the rendering engine to processing CSS styles and executing JavaScript. You can also specify custom headers when converting a specified URL. The library provides rich code samples.

What Are the Key Differences in PDF Conversion Capabilities?

Feature	PuppeteerSharp	wkhtmltopdf	IronPDF
CSS3 Support	Full	Limited	Full
JavaScript Rendering	Yes	Basic	Yes
Installation Size	~150MB	~40MB	~20MB
External Dependencies	Chromium	Qt WebKit	None
API Complexity	Moderate	High	Simple
PDF/A Support	No	No	Yes
Headers/Footers	Manual Setup	Yes	Built-in
Watermarks	Manual	No	Built-in
Form Creation	No	No	Yes
Page Manipulation	Limited	No	Full
Commercial Support	No	No	Yes

How Do These Libraries Handle Complex HTML Content?

When converting HTML strings with embedded CSS and JavaScript, the differences become apparent. PuppeteerSharp requires async/await patterns and explicit browser management to achieve accurate HTML rendering:

// PuppeteerSharp - Complex setup for simple tasks
await page.WaitForSelectorAsync(".content");
await page.EvaluateFunctionAsync("() => window.scrollTo(0, document.body.scrollHeight)");
await page.WaitForTimeoutAsync(2000); // Wait for JavaScript

// PuppeteerSharp - Complex setup for simple tasks
await page.WaitForSelectorAsync(".content");
await page.EvaluateFunctionAsync("() => window.scrollTo(0, document.body.scrollHeight)");
await page.WaitForTimeoutAsync(2000); // Wait for JavaScript

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

IronPDF simplifies this with intelligent defaults:

// IronPDF - Automatic handling of complex content
renderer.RenderingOptions.WaitFor.JavaScript();
var pdf = renderer.RenderHtmlAsPdf(complexHtml);

// IronPDF - Automatic handling of complex content
renderer.RenderingOptions.WaitFor.JavaScript();
var pdf = renderer.RenderHtmlAsPdf(complexHtml);

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

Which Solution Fits Your PDF Generation Needs?

For simple PDF generation tasks with basic dynamic content, open-source solutions like PuppeteerSharp can work well. However, they come with hidden costs: complex deployment, ongoing maintenance, and limited features for manipulating existing PDFs.

IronPDF excels when you need:

Reliable HTML to PDF conversion with consistent results
Advanced features like PDF/A compliance, digital signatures, and form creation
Simplified, intuitive API that reduces development time
Professional support for production environments

The library offers a free version trial to evaluate its capabilities, with licensing starting at competitive rates for small teams. The trial includes a free limited key.

Start Creating High-Quality PDF Files

Whether you choose an open-source solution or IronPDF depends on your specific requirements. Open-source libraries offer zero licensing fees but require more development effort and have limitations in features and support. IronPDF provides a comprehensive solution that can easily convert HTML content to professional PDF documents with just a few lines of code.

For developers seeking to generate PDF documents efficiently while maintaining high quality, IronPDF's combination of powerful features and simple API makes it a compelling choice. You can download IronPDF via NuGet Package Manager and start converting HTML to PDF immediately:

Install-Package IronPdf

Transform your HTML strings, files, and web pages into pixel-perfect PDF documents today with the solution that best fits your project's needs.

Frequently Asked Questions

What are the advantages of using IronPDF over open-source HTML to PDF libraries?

IronPDF offers robust features such as precise rendering, support for complex CSS and JavaScript, and excellent performance, making it ideal for large-scale PDF generation projects in .NET.

Can IronPDF handle complex web pages when converting HTML to PDF?

Yes, IronPDF is designed to handle complex web pages, including those with intricate CSS and JavaScript, ensuring accurate and high-quality PDF conversions.

How does IronPDF improve the development process for .NET projects?

IronPDF streamlines the development process by providing reliable and efficient HTML to PDF conversion, reducing the time and effort required to integrate PDF generation into .NET applications.

Is IronPDF suitable for generating large-scale PDF documents?

Absolutely, IronPDF is built to handle large-scale PDF generation efficiently, making it suitable for projects requiring high-volume PDF creation.

Does IronPDF support custom PDF generation features?

Yes, IronPDF supports various custom features such as setting headers, footers, and watermarks, allowing for tailored PDF document creation.

What kind of support does IronPDF offer compared to open-source libraries?

IronPDF provides professional support and regular updates, ensuring that developers have access to the latest features and assistance, unlike many open-source alternatives.

How does IronPDF ensure high-quality PDF output?

IronPDF uses advanced rendering technology to ensure that the converted PDFs maintain high quality, accurately reflecting the original HTML content.

Is there a performance difference between IronPDF and open-source HTML to PDF converters?

Yes, IronPDF typically offers superior performance with faster conversion speeds and better resource management compared to many open-source converters.

Can I integrate IronPDF into existing .NET applications easily?

IronPDF is designed for easy integration into existing .NET applications, providing a straightforward API that minimizes the effort required to add PDF functionality.

What types of projects benefit most from using IronPDF?

Projects requiring frequent, high-quality PDF generation, such as invoicing systems, reporting tools, and web archiving applications, benefit greatly from using IronPDF.

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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