COMPARISON

PDFreactor vs IronPDF: Technical Comparison Guide

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When .NET developers need to convert HTML to PDF, they encounter libraries with fundamentally different architectures. PDFreactor operates as a Java-based conversion server with excellent CSS Paged Media support, while IronPDF provides a native .NET library with an embedded Chromium engine. This comparison examines both solutions, analyzing their architectural differences, integration complexity, and suitability for different application requirements.

What Is PDFreactor?

PDFreactor is a strong HTML-to-PDF conversion server that uses proprietary technology to convert HTML and CSS content into high-quality PDF documents. The library supports many CSS properties, including advanced CSS Paged Media specifications, making it a good choice for complex layout rendering requiring the highest fidelity.

PDFreactor runs as a separate Java-based service, and .NET applications communicate with it through REST API calls or socket connections. The library uses a Configuration object pattern where settings and HTML content are bundled together and sent to the server for processing.

Key characteristics of PDFreactor include:

  • Java-Based Server: Runs as a separate service requiring Java Runtime Environment
  • CSS Paged Media Support: Excellent support for CSS3 and CSS Paged Media specifications
  • Server Architecture: Requires REST API or socket communication from .NET applications
  • Configuration Object Pattern: Uses Configuration objects to bundle settings and content
  • High-Fidelity Rendering: Optimized for complex, print-quality document layouts
  • Cross-Platform via Java: Runs on any system with Java installed

What Is IronPDF?

IronPDF is a complete native .NET library that provides full PDF lifecycle management. The ChromePdfRenderer class uses an embedded Chromium rendering engine for HTML-to-PDF conversion, providing full CSS3 and JavaScript support without external dependencies.

Unlike PDFreactor's server architecture, IronPDF runs in-process within your .NET application. This eliminates Java dependencies, server infrastructure, and network latency—converting HTML to PDF becomes a simple method call rather than an HTTP request.

Architectural Comparison

The fundamental difference between PDFreactor and IronPDF lies in their architecture: external Java server versus native .NET library.

AspectPDFreactorIronPDF
RuntimeJava (external server)Native .NET (in-process)
ArchitectureREST API serviceNuGet library
DeploymentJava + server configurationSingle NuGet package
DependenciesJRE + HTTP clientSelf-contained
LatencyNetwork round-tripDirect method calls
CSS SupportCSS Paged MediaChromium engine
PDF ManipulationConversion onlyFull lifecycle
Native .NET LibraryNo (Java-based)Yes
Cross-Platform CapabilityYes (Java-dependent)Yes (Bundled Chromium)
Deployment ComplexityMore complex due to JavaSimple, directly integrates with .NET

For teams working in .NET environments, PDFreactor's Java dependency creates significant deployment complexity—two runtimes to manage in CI/CD pipelines, separate infrastructure to monitor and maintain, and network latency on every conversion.

HTML to PDF Conversion

Converting HTML content to PDF demonstrates the different patterns between these libraries.

PDFreactor HTML-to-PDF approach:

// NuGet: Install-Package PDFreactor.Native.Windows.x64
using RealObjects.PDFreactor;
using System.IO;

class Program
{
    static void Main()
    {
        PDFreactor pdfReactor = new PDFreactor();

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

        Configuration config = new Configuration();
        config.Document = html;

        Result result = pdfReactor.Convert(config);

        File.WriteAllBytes("output.pdf", result.Document);
    }
}
// NuGet: Install-Package PDFreactor.Native.Windows.x64
using RealObjects.PDFreactor;
using System.IO;

class Program
{
    static void Main()
    {
        PDFreactor pdfReactor = new PDFreactor();

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

        Configuration config = new Configuration();
        config.Document = html;

        Result result = pdfReactor.Convert(config);

        File.WriteAllBytes("output.pdf", result.Document);
    }
}
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IronPDF HTML-to-PDF approach:

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

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();

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

        var pdf = renderer.RenderHtmlAsPdf(html);

        pdf.SaveAs("output.pdf");
    }
}
// NuGet: Install-Package IronPdf
using IronPdf;
using System;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();

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

        var pdf = renderer.RenderHtmlAsPdf(html);

        pdf.SaveAs("output.pdf");
    }
}
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PDFreactor uses a Configuration object where HTML content is assigned to the Document property, then passed to the Convert() method which returns a Result object. The PDF bytes are accessed via result.Document and must be written to disk using File.WriteAllBytes().

IronPDF's ChromePdfRenderer uses RenderHtmlAsPdf() which directly accepts HTML and returns a PdfDocument object with a SaveAs() method. This pattern eliminates the configuration object ceremony and provides a more intuitive API. For detailed guidance on HTML-to-PDF conversion, see the HTML to PDF tutorial.

URL to PDF Conversion

Converting web pages to PDF shows similar pattern differences.

PDFreactor URL-to-PDF approach:

// NuGet: Install-Package PDFreactor.Native.Windows.x64
using RealObjects.PDFreactor;
using System.IO;

class Program
{
    static void Main()
    {
        PDFreactor pdfReactor = new PDFreactor();

        Configuration config = new Configuration();
        config.Document = "https://www.example.com";

        Result result = pdfReactor.Convert(config);

        File.WriteAllBytes("webpage.pdf", result.Document);
    }
}
// NuGet: Install-Package PDFreactor.Native.Windows.x64
using RealObjects.PDFreactor;
using System.IO;

class Program
{
    static void Main()
    {
        PDFreactor pdfReactor = new PDFreactor();

        Configuration config = new Configuration();
        config.Document = "https://www.example.com";

        Result result = pdfReactor.Convert(config);

        File.WriteAllBytes("webpage.pdf", result.Document);
    }
}
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IronPDF URL-to-PDF approach:

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

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();

        var pdf = renderer.RenderUrlAsPdf("https://www.example.com");

        pdf.SaveAs("webpage.pdf");
    }
}
// NuGet: Install-Package IronPdf
using IronPdf;
using System;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();

        var pdf = renderer.RenderUrlAsPdf("https://www.example.com");

        pdf.SaveAs("webpage.pdf");
    }
}
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PDFreactor uses the same Configuration.Document property for both HTML strings and URLs—the library determines the content type automatically. IronPDF provides a dedicated RenderUrlAsPdf() method that explicitly indicates the operation being performed, making code more self-documenting. Learn more about URL to PDF conversion in the IronPDF documentation.

Headers and Footers

Adding headers and footers reveals fundamentally different approaches between the libraries.

PDFreactor headers and footers (CSS Paged Media):

// NuGet: Install-Package PDFreactor.Native.Windows.x64
using RealObjects.PDFreactor;
using System.IO;

class Program
{
    static void Main()
    {
        PDFreactor pdfReactor = new PDFreactor();

        string html = "<html><body><h1>Document with Headers</h1><p>Content here</p></body></html>";

        Configuration config = new Configuration();
        config.Document = html;
        config.AddUserStyleSheet("@page { @top-center { content: 'Header Text'; } @bottom-center { content: 'Page ' counter(page); } }");

        Result result = pdfReactor.Convert(config);

        File.WriteAllBytes("document.pdf", result.Document);
    }
}
// NuGet: Install-Package PDFreactor.Native.Windows.x64
using RealObjects.PDFreactor;
using System.IO;

class Program
{
    static void Main()
    {
        PDFreactor pdfReactor = new PDFreactor();

        string html = "<html><body><h1>Document with Headers</h1><p>Content here</p></body></html>";

        Configuration config = new Configuration();
        config.Document = html;
        config.AddUserStyleSheet("@page { @top-center { content: 'Header Text'; } @bottom-center { content: 'Page ' counter(page); } }");

        Result result = pdfReactor.Convert(config);

        File.WriteAllBytes("document.pdf", result.Document);
    }
}
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IronPDF headers and footers (API-based):

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

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();

        renderer.RenderingOptions.TextHeader = new TextHeaderFooter()
        {
            CenterText = "Header Text"
        };

        renderer.RenderingOptions.TextFooter = new TextHeaderFooter()
        {
            CenterText = "Page {page}"
        };

        string html = "<html><body><h1>Document with Headers</h1><p>Content here</p></body></html>";

        var pdf = renderer.RenderHtmlAsPdf(html);

        pdf.SaveAs("document.pdf");
    }
}
// NuGet: Install-Package IronPdf
using IronPdf;
using IronPdf.Rendering;
using System;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();

        renderer.RenderingOptions.TextHeader = new TextHeaderFooter()
        {
            CenterText = "Header Text"
        };

        renderer.RenderingOptions.TextFooter = new TextHeaderFooter()
        {
            CenterText = "Page {page}"
        };

        string html = "<html><body><h1>Document with Headers</h1><p>Content here</p></body></html>";

        var pdf = renderer.RenderHtmlAsPdf(html);

        pdf.SaveAs("document.pdf");
    }
}
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PDFreactor uses CSS Paged Media syntax with @page rules and @top-center/@bottom-center regions. The counter(page) function provides page numbers. This approach leverages CSS standards but requires CSS knowledge and string-based configuration via AddUserStyleSheet().

IronPDF uses a dedicated API with TextHeaderFooter objects assigned to RenderingOptions. The {page} placeholder provides page numbers. This approach provides IntelliSense support, compile-time checking, and more discoverable API. For comprehensive header/footer implementation, see the headers and footers documentation.

API Mapping Reference

For teams evaluating PDFreactor migration to IronPDF, understanding the API mappings helps estimate development effort.

Core Classes

PDFreactorIronPDF
PDFreactorChromePdfRenderer
ConfigurationChromePdfRenderOptions
ResultPdfDocument
config.DocumentRenderHtmlAsPdf(html)
result.Document (byte[])pdf.BinaryData

Configuration Properties

PDFreactor ConfigurationIronPDF RenderingOptions
config.Document = htmlrenderer.RenderHtmlAsPdf(html)
config.Document = urlrenderer.RenderUrlAsPdf(url)
config.PageFormat = PageFormat.A4RenderingOptions.PaperSize = PdfPaperSize.A4
config.PageOrientationRenderingOptions.PaperOrientation
config.PageMarginsRenderingOptions.MarginTop/Bottom/Left/Right
config.EnableJavaScript = trueRenderingOptions.EnableJavaScript = true
config.AddUserStyleSheet(css)Embed CSS in HTML
config.Titlepdf.MetaData.Title
config.Encryptionpdf.SecuritySettings

Features Unavailable in PDFreactor

IronPDF FeatureDescription
PdfDocument.Merge()Combine multiple PDFs
pdf.ApplyWatermark()Add watermarks
pdf.ExtractAllText()Extract text content
pdf.CopyPages(start, end)Extract specific pages
pdf.SecuritySettingsPassword protection and encryption
pdf.Sign(certificate)Digital signatures
pdf.Form.GetFieldByName(name).ValueForm filling

PDFreactor focuses on conversion only, while IronPDF provides complete PDF lifecycle management. For PDF manipulation features, see the merge and split PDFs guide.

The Java Dependency Problem

PDFreactor's Java-based architecture creates significant challenges in .NET environments:

  • Java Runtime Required: Must install and maintain JRE/JDK on all servers
  • Server Architecture: Runs as a separate service requiring REST API calls
  • Complex Deployment: Two runtimes (Java + .NET) to manage in CI/CD pipelines
  • Network Latency: Every PDF conversion requires HTTP round-trip to server
  • Separate Infrastructure: Additional server to monitor, scale, and maintain
  • License Complexity: Per-server licensing tied to Java service instance
  • Operational Overhead: Two runtimes to maintain, monitor, and update

IronPDF eliminates these challenges by running in-process as a native .NET library. No Java installation, no server configuration, no network latency—just a NuGet package reference.

Feature Comparison Summary

Feature/AspectPDFreactorIronPDF
Native .NET LibraryNo (Java-based)Yes
Cross-Platform CapabilityYes (Java-dependent)Yes (Bundled Chromium)
CSS SupportAdvanced support for CSS3, CSS Paged MediaComprehensive HTML5/CSS3 via Chromium
Deployment ComplexityMore complex due to JavaSimple, directly integrates with .NET
PDF Manipulation FeaturesBasic (Generation only)Extensive (merge, split, edit, annotate)
Licensing ModelCommercialCommercial
Primary Use CaseHigh fidelity, complex documentsBroad use, ease-of-use in .NET apps
Headers/FootersCSS Paged Media (@page rules)API-based (TextHeaderFooter objects)
JavaScript ExecutionSupportedSupported (Chromium engine)

Applications requiring watermarking, PDF merging, text extraction, or form filling cannot achieve these with PDFreactor alone.

CSS Paged Media vs API-Based Approach

PDFreactor's strength lies in CSS Paged Media support—using standard CSS rules like @page, @top-center, and counter(page) for document formatting. This approach benefits teams with strong CSS expertise.

IronPDF uses an API-based approach with dedicated objects like TextHeaderFooter and HtmlHeaderFooter. This provides:

  • IntelliSense support for discoverability
  • Compile-time type checking
  • No string-based CSS to maintain
  • Easier debugging and testing

Teams must evaluate whether CSS Paged Media expertise exists or whether API-based configuration is preferable.

When Teams Consider Moving from PDFreactor to IronPDF

Several factors drive teams to evaluate IronPDF as an alternative to PDFreactor:

Deployment Simplification: PDFreactor requires Java runtime installation, server configuration, and REST API integration. IronPDF deploys as a single NuGet package with no external dependencies.

Infrastructure Reduction: PDFreactor requires separate server infrastructure to host the Java service. IronPDF runs in-process, eliminating additional servers to monitor and maintain.

Native .NET Integration: PDFreactor's Java architecture creates integration friction in .NET environments. IronPDF provides a native .NET API with familiar patterns.

PDF Manipulation Needs: PDFreactor focuses on conversion. Applications requiring document manipulation (merging, splitting, watermarking) need IronPDF's extended capabilities.

CI/CD Simplification: Managing Java dependencies in .NET CI/CD pipelines adds complexity. IronPDF simplifies pipelines to standard NuGet restore.

Latency Reduction: PDFreactor's network round-trips add latency to every conversion. IronPDF's in-process architecture eliminates network overhead.

Installation Comparison

PDFreactor installation:

Install-Package PDFreactor.Native.Windows.x64
Install-Package PDFreactor.Native.Windows.x64
SHELL

Plus Java runtime installation and server configuration.

IronPDF installation:

Install-Package IronPdf
Install-Package IronPdf
SHELL

IronPDF requires a license key configuration:

IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";
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IronPDF's first run downloads the Chromium rendering engine (~150MB one-time). For Linux deployments, additional system dependencies are required. The library supports .NET Framework, .NET Core, .NET 5+, and forward compatibility into .NET 10 and C# 14.

Making the Decision

The choice between PDFreactor and IronPDF depends on your project requirements and existing infrastructure:

Consider PDFreactor if: Your project demands high-fidelity rendering with extensive CSS Paged Media support, your team has strong CSS expertise, you can handle Java dependencies, and conversion-only functionality is sufficient.

Consider IronPDF if: You're developing within a .NET environment and desire smooth integration, you want to eliminate Java dependencies and server infrastructure, you need PDF manipulation beyond conversion, you prefer API-based configuration over CSS strings, or you want simplified deployment and CI/CD pipelines.

For most modern .NET applications—especially those prioritizing deployment simplicity, native integration, and extended PDF capabilities—IronPDF provides significant architectural advantages over PDFreactor's Java-based server approach.

Getting Started with IronPDF

To evaluate IronPDF for your PDF generation needs:

  1. Install via NuGet: Install-Package IronPdf
  2. Review the getting started documentation
  3. Explore HTML to PDF tutorials for conversion patterns
  4. Check the API reference for complete method documentation

The IronPDF tutorials provide comprehensive examples covering common scenarios from basic conversion to advanced PDF manipulation.