COMPARISON

DinkToPdf vs IronPDF: Technical Comparison Guide

When .NET developers assess PDF generation libraries, DinkToPdf is a well-known open-source choice that uses the wkhtmltopdf binary. However, significant security vulnerabilities, thread safety concerns, and a lack of ongoing maintenance prompt many teams to consider alternatives. IronPDF provides a modern, actively maintained solution with a Chromium rendering engine and no native binary dependencies.

This comparison looks at both libraries across relevant technical aspects to assist professional developers and architects in making informed decisions for their .NET PDF needs.

Understanding DinkToPdf

DinkToPdf is an open-source library in the C# ecosystem that enables HTML-to-PDF conversion using a wrapper around wkhtmltopdf. The library uses the MIT license, making it accessible for integration and modification in various projects.

DinkToPdf encapsulates the functionality of wkhtmltopdf, allowing developers to convert HTML content with CSS and JavaScript into PDF documents. However, the library inherits all security vulnerabilities and limitations associated with the wkhtmltopdf binary, including the critical CVE-2022-35583 SSRF (Server-Side Request Forgery) issue. The wkhtmltopdf project has been abandoned since 2020, and DinkToPdf itself last received updates in 2018.

The library requires deployment of platform-specific native binaries (libwkhtmltox.dll for Windows, libwkhtmltox.so for Linux, libwkhtmltox.dylib for macOS), creating deployment complexity and maintenance overhead. Additionally, DinkToPdf is notably non-thread-safe, leading to documented failures in concurrent execution environments even when using the SynchronizedConverter wrapper.

Understanding IronPDF

IronPDF is a commercial .NET PDF library that uses a modern Chromium rendering engine for HTML-to-PDF conversion. The library provides complete PDF generation and manipulation capabilities without reliance on external native binaries.

IronPDF supports .NET Framework 4.6.2+, .NET Core 3.1+, and .NET 5/6/7/8/9, with a pure NuGet package deployment model that eliminates native dependency management. The library is designed for thread-safe concurrent operations, enabling reliable parallel PDF generation without the crashes associated with DinkToPdf.

Security Comparison

The security implications represent the most significant difference between these .NET PDF libraries.

Security AspectDinkToPdfIronPDF
Known VulnerabilitiesCVE-2022-35583 (SSRF)No known vulnerabilities
Vulnerability StatusUnpatchedMitigated by design
Core Dependencywkhtmltopdf (abandoned 2020)Modern Chromium
Security UpdatesNone (project abandoned)Regular updates

DinkToPdf inherits the CVE-2022-35583 Server-Side Request Forgery vulnerability from wkhtmltopdf. This vulnerability allows attackers to access internal network resources, creating significant security risks for applications processing untrusted HTML content. Given wkhtmltopdf's abandoned status, these vulnerabilities will never receive patches.

Architecture and Rendering Engine Comparison

AspectDinkToPdfIronPDF
Rendering EngineOutdated WebKit (circa 2015)Modern Chromium
Thread SafetyCrashes in concurrent useFully thread-safe
Native DependenciesPlatform-specific binariesPure NuGet package
CSS SupportNo Flexbox/GridFull CSS3
JavaScriptLimited, inconsistentSupported
MaintenanceAbandoned (2018)Actively maintained
SupportCommunity onlyProfessional support

DinkToPdf's wkhtmltopdf dependency uses an outdated WebKit engine from approximately 2015. This creates rendering limitations where modern CSS features like Flexbox and Grid layouts fail to render correctly. JavaScript execution is limited and inconsistent, producing unreliable results for dynamic content.

IronPDF uses a modern Chromium engine that renders HTML exactly as contemporary browsers display it, with full CSS3 support including Flexbox and Grid layouts, and reliable JavaScript execution with configurable wait times.

Code Comparison: Common PDF Operations

Basic HTML to PDF Conversion

The most fundamental operation demonstrates the API complexity differences.

DinkToPdf:

// NuGet: Install-Package DinkToPdf
using DinkToPdf;
using DinkToPdf.Contracts;
using System.IO;

class Program
{
    static void Main()
    {
        var converter = new SynchronizedConverter(new PdfTools());
        var doc = new HtmlToPdfDocument()
        {
            GlobalSettings = {
                ColorMode = ColorMode.Color,
                Orientation = Orientation.Portrait,
                PaperSize = PaperKind.A4,
            },
            Objects = {
                new ObjectSettings() {
                    HtmlContent = "<h1>Hello World</h1><p>This is a PDF from HTML.</p>",
                    WebSettings = { DefaultEncoding = "utf-8" }
                }
            }
        };
        byte[] pdf = converter.Convert(doc);
        File.WriteAllBytes("output.pdf", pdf);
    }
}
// NuGet: Install-Package DinkToPdf
using DinkToPdf;
using DinkToPdf.Contracts;
using System.IO;

class Program
{
    static void Main()
    {
        var converter = new SynchronizedConverter(new PdfTools());
        var doc = new HtmlToPdfDocument()
        {
            GlobalSettings = {
                ColorMode = ColorMode.Color,
                Orientation = Orientation.Portrait,
                PaperSize = PaperKind.A4,
            },
            Objects = {
                new ObjectSettings() {
                    HtmlContent = "<h1>Hello World</h1><p>This is a PDF from HTML.</p>",
                    WebSettings = { DefaultEncoding = "utf-8" }
                }
            }
        };
        byte[] pdf = converter.Convert(doc);
        File.WriteAllBytes("output.pdf", pdf);
    }
}
$vbLabelText   $csharpLabel

IronPDF:

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

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        var pdf = renderer.RenderHtmlAsPdf("<h1>Hello World</h1><p>This is a PDF from HTML.</p>");
        pdf.SaveAs("output.pdf");
    }
}
// NuGet: Install-Package IronPdf
using IronPdf;
using System;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        var pdf = renderer.RenderHtmlAsPdf("<h1>Hello World</h1><p>This is a PDF from HTML.</p>");
        pdf.SaveAs("output.pdf");
    }
}
$vbLabelText   $csharpLabel

DinkToPdf requires creating a SynchronizedConverter with PdfTools, constructing an HtmlToPdfDocument with GlobalSettings and ObjectSettings, configuring WebSettings, converting to byte[], and manually writing to a file. IronPDF creates a ChromePdfRenderer, calls RenderHtmlAsPdf(), and saves—three lines versus fifteen.

For advanced HTML rendering options, explore the HTML to PDF conversion guide.

URL to PDF Conversion

Capturing web pages as PDFs shows similar complexity differences.

DinkToPdf:

// NuGet: Install-Package DinkToPdf
using DinkToPdf;
using DinkToPdf.Contracts;
using System.IO;

class Program
{
    static void Main()
    {
        var converter = new SynchronizedConverter(new PdfTools());
        var doc = new HtmlToPdfDocument()
        {
            GlobalSettings = {
                ColorMode = ColorMode.Color,
                Orientation = Orientation.Portrait,
                PaperSize = PaperKind.A4,
            },
            Objects = {
                new ObjectSettings() {
                    Page = "https://www.example.com",
                }
            }
        };
        byte[] pdf = converter.Convert(doc);
        File.WriteAllBytes("webpage.pdf", pdf);
    }
}
// NuGet: Install-Package DinkToPdf
using DinkToPdf;
using DinkToPdf.Contracts;
using System.IO;

class Program
{
    static void Main()
    {
        var converter = new SynchronizedConverter(new PdfTools());
        var doc = new HtmlToPdfDocument()
        {
            GlobalSettings = {
                ColorMode = ColorMode.Color,
                Orientation = Orientation.Portrait,
                PaperSize = PaperKind.A4,
            },
            Objects = {
                new ObjectSettings() {
                    Page = "https://www.example.com",
                }
            }
        };
        byte[] pdf = converter.Convert(doc);
        File.WriteAllBytes("webpage.pdf", pdf);
    }
}
$vbLabelText   $csharpLabel

IronPDF:

// 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");
    }
}
$vbLabelText   $csharpLabel

DinkToPdf uses the Page property within ObjectSettings to specify a URL, requiring the same document wrapper structure. IronPDF provides a dedicated RenderUrlAsPdf() method for direct URL rendering.

Learn more about URL rendering in the URL to PDF documentation.

Custom Page Settings and Margins

Configuring page orientation and margins demonstrates settings API differences.

DinkToPdf:

// NuGet: Install-Package DinkToPdf
using DinkToPdf;
using DinkToPdf.Contracts;
using System.IO;

class Program
{
    static void Main()
    {
        var converter = new SynchronizedConverter(new PdfTools());
        var doc = new HtmlToPdfDocument()
        {
            GlobalSettings = {
                ColorMode = ColorMode.Color,
                Orientation = Orientation.Landscape,
                PaperSize = PaperKind.A4,
                Margins = new MarginSettings { Top = 10, Bottom = 10, Left = 15, Right = 15 }
            },
            Objects = {
                new ObjectSettings() {
                    HtmlContent = "<h1>Custom PDF</h1><p>Landscape orientation with custom margins.</p>",
                    WebSettings = { DefaultEncoding = "utf-8" }
                }
            }
        };
        byte[] pdf = converter.Convert(doc);
        File.WriteAllBytes("custom.pdf", pdf);
    }
}
// NuGet: Install-Package DinkToPdf
using DinkToPdf;
using DinkToPdf.Contracts;
using System.IO;

class Program
{
    static void Main()
    {
        var converter = new SynchronizedConverter(new PdfTools());
        var doc = new HtmlToPdfDocument()
        {
            GlobalSettings = {
                ColorMode = ColorMode.Color,
                Orientation = Orientation.Landscape,
                PaperSize = PaperKind.A4,
                Margins = new MarginSettings { Top = 10, Bottom = 10, Left = 15, Right = 15 }
            },
            Objects = {
                new ObjectSettings() {
                    HtmlContent = "<h1>Custom PDF</h1><p>Landscape orientation with custom margins.</p>",
                    WebSettings = { DefaultEncoding = "utf-8" }
                }
            }
        };
        byte[] pdf = converter.Convert(doc);
        File.WriteAllBytes("custom.pdf", pdf);
    }
}
$vbLabelText   $csharpLabel

IronPDF:

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

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        renderer.RenderingOptions.PaperOrientation = PdfPaperOrientation.Landscape;
        renderer.RenderingOptions.MarginTop = 10;
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.MarginLeft = 15;
        renderer.RenderingOptions.MarginRight = 15;

        var pdf = renderer.RenderHtmlAsPdf("<h1>Custom PDF</h1><p>Landscape orientation with custom margins.</p>");
        pdf.SaveAs("custom.pdf");
    }
}
// NuGet: Install-Package IronPdf
using IronPdf;
using IronPdf.Rendering;
using System;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        renderer.RenderingOptions.PaperOrientation = PdfPaperOrientation.Landscape;
        renderer.RenderingOptions.MarginTop = 10;
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.MarginLeft = 15;
        renderer.RenderingOptions.MarginRight = 15;

        var pdf = renderer.RenderHtmlAsPdf("<h1>Custom PDF</h1><p>Landscape orientation with custom margins.</p>");
        pdf.SaveAs("custom.pdf");
    }
}
$vbLabelText   $csharpLabel

DinkToPdf embeds page settings within GlobalSettings including a nested MarginSettings object. IronPDF uses RenderingOptions properties directly on the renderer, with individual margin properties (MarginTop, MarginBottom, MarginLeft, MarginRight) for clearer configuration.

Method Mapping Reference

For developers evaluating DinkToPdf migration or comparing capabilities, this mapping shows equivalent operations:

Core Class Mapping

DinkToPdfIronPDF
SynchronizedConverterChromePdfRenderer
BasicConverterChromePdfRenderer
PdfToolsNot needed
HtmlToPdfDocumentNot needed
GlobalSettingsRenderingOptions
ObjectSettingsRenderingOptions
MarginSettingsIndividual margin properties

Settings Mapping

DinkToPdfIronPDF
GlobalSettings.PaperSizeRenderingOptions.PaperSize
GlobalSettings.OrientationRenderingOptions.PaperOrientation
GlobalSettings.Margins.Top = 10RenderingOptions.MarginTop = 10
ObjectSettings.HtmlContentRenderHtmlAsPdf(html)
ObjectSettings.PageRenderUrlAsPdf(url)
converter.Convert(doc) returns byte[]pdf.BinaryData or pdf.SaveAs()
DinkToPdfIronPDF
[page]{page}
[toPage]{total-pages}
[date]{date}
[time]{time}
[title]{html-title}

Feature Comparison Summary

FeatureDinkToPdfIronPDF
HTML to PDF✅ (outdated engine)✅ (Chromium)
URL to PDF
Custom margins
Headers/Footers✅ (limited)✅ (full HTML)
CSS3❌ Limited✅ Full
Flexbox/Grid
JavaScript⚠️ Limited✅ Full
PDF manipulation
Form filling
Digital signatures
Encryption
Watermarks
Merge/Split

When Teams Consider Moving from DinkToPdf to IronPDF

Development teams evaluate transitioning from DinkToPdf to IronPDF for several reasons:

Security Compliance Requirements: The CVE-2022-35583 SSRF vulnerability in wkhtmltopdf creates unacceptable risk for applications processing untrusted HTML content. Security audits flag this vulnerability, and with no patches available, teams must migrate to address compliance requirements.

Thread Safety Problems: DinkToPdf crashes in concurrent execution environments even when using SynchronizedConverter. Production applications requiring parallel PDF generation experience reliability issues that cannot be resolved within DinkToPdf's architecture.

Modern CSS Requirements: Applications using contemporary CSS layouts (Flexbox, Grid) find DinkToPdf's outdated WebKit engine incapable of rendering these layouts correctly. Teams building modern web interfaces cannot generate accurate PDF representations.

Native Binary Management: The requirement for platform-specific libwkhtmltox binaries creates deployment complexity across Windows, Linux, and macOS environments. Container deployments and CI/CD pipelines require additional configuration for native dependencies.

Abandoned Maintenance: With DinkToPdf's last update in 2018 and wkhtmltopdf abandoned since 2020, teams cannot rely on bug fixes, security patches, or compatibility updates for modern .NET versions.

JavaScript Reliability: Applications generating PDFs from dynamic content experience inconsistent JavaScript execution with DinkToPdf. IronPDF's Chromium engine provides reliable JavaScript execution with configurable wait times.

Strengths and Considerations

DinkToPdf Strengths

  • Open Source: MIT license allows free use and modification
  • Simplicity: Basic HTML-to-PDF conversion for simple use cases
  • Community: Established user base with community resources

DinkToPdf Considerations

  • Security Vulnerabilities: CVE-2022-35583 SSRF vulnerability, unpatched
  • Abandoned Project: No updates since 2018, wkhtmltopdf abandoned since 2020
  • Thread Safety: Crashes in concurrent use despite SynchronizedConverter
  • Native Dependencies: Platform-specific binaries required
  • Outdated Rendering: WebKit engine from 2015 without Flexbox/Grid support
  • Limited JavaScript: Inconsistent execution

IronPDF Strengths

  • Modern Rendering: Chromium engine with full CSS3 and JavaScript support
  • Thread Safety: Designed for concurrent operations
  • No Native Dependencies: Pure NuGet package deployment
  • Active Maintenance: Regular updates and security patches
  • Professional Support: Enterprise-grade support available
  • Extended Features: PDF manipulation, forms, signatures, encryption, watermarks
  • Extensive Resources: Comprehensive tutorials and documentation

IronPDF Considerations

  • Commercial License: Requires license for production use

Conclusion

DinkToPdf and IronPDF represent fundamentally different approaches to PDF generation in .NET applications. DinkToPdf offers open-source accessibility but carries critical security vulnerabilities, thread safety issues, and an abandoned maintenance status that create significant production risks.

IronPDF provides a modern alternative with a Chromium rendering engine, thread-safe architecture, no native dependencies, and active maintenance. For teams requiring security compliance, concurrent PDF generation, modern CSS support, or reliable JavaScript execution, IronPDF addresses these specific requirements.

As organizations plan for .NET 10, C# 14, and application development through 2026, the choice between abandoned libraries with known vulnerabilities and actively maintained solutions affects both immediate functionality and long-term security posture. Teams should evaluate their specific requirements—security compliance, concurrency needs, CSS complexity, and deployment constraints—against each library's characteristics.

Start evaluating IronPDF with a free trial and explore the comprehensive documentation to assess fit for your specific requirements.