How to Add Images to PDFs in C# with IronPDF

Why Does the RenderHtmlAsPdf Method Work Best?

The RenderHtmlAsPdf method leverages IronPDF's Chrome rendering engine to convert HTML content, including images, into PDF format while preserving layout and styling. This method supports responsive CSS layouts and ensures images render as they appear in a web browser. For complex layouts, see our guide on pixel-perfect HTML formatting.

What Image Formats Are Supported?

IronPDF supports all major image formats including PNG, JPG, SVG, GIF, and BMP when embedding through HTML conversion. The library handles SVG graphics effectively for scalable vector illustrations. When working with different formats, ensure your HTML properly specifies the image type in the src attribute or Base64 data URI.

When Should I Use Direct URL vs Base64 Encoding?

Use direct URLs when images are hosted online and file size is a concern. Choose Base64 encoding for self-contained PDFs that don't require internet access. For images stored in cloud services, see our guide on embedding images from Azure Blob Storage. This decision impacts both file size and portability of your generated PDFs.

:path=/static-assets/pdf/content-code-examples/how-to/add-images-to-pdfs-embed-image.cs

using IronPdf;

ChromePdfRenderer renderer = new ChromePdfRenderer();

string html = @"<img src='https://ironsoftware.com/img/products/ironpdf-logo-text-dotnet.svg'>";

// Render HTML to PDF
PdfDocument pdf = renderer.RenderHtmlAsPdf(html);

// Export PDF
pdf.SaveAs("embedImage.pdf");

Why Use Base64 Encoding for Images?

Base64 encoding creates self-contained PDFs that don't rely on external resources, ensuring images always display without internet connectivity or when original image files are moved or deleted. This technique is useful when creating PDFs in Blazor Server applications or when deploying to Azure where external file access might be restricted. The encoded images become part of the HTML string, making them ideal for HTML string to PDF conversions.

What Are the Performance Considerations?

Base64 encoding increases file size by approximately 33% but eliminates external dependencies, making it ideal for archival purposes or restricted network environments. When performance is critical, consider using async PDF generation to handle multiple image conversions concurrently. For large-scale operations, see our performance optimization guide to maximize throughput.

How Do I Handle Large Image Files?

For large images, compress them before Base64 encoding to minimize PDF file size, or use external URLs if file size is critical. IronPDF offers PDF compression features that can reduce file sizes by up to 75%. When working with multiple images, optimize your rendering settings for the best balance between quality and file size.

:path=/static-assets/pdf/content-code-examples/how-to/add-images-to-pdfs-base64-image.cs

using IronPdf;
using System;
using System.IO;

ChromePdfRenderer renderer = new ChromePdfRenderer();

// Import image file binary data
byte[] binaryData = File.ReadAllBytes("ironpdf-logo-text-dotnet.svg");

// Convert the binary data to base 64
string imgDataUri = Convert.ToBase64String(binaryData);

// Embed in HTML
string html = $"<img src='data:image/svg+xml;base64,{imgDataUri}'>";

// Convert HTML to PDF
PdfDocument pdf = renderer.RenderHtmlAsPdf(html);

// Export the PDF
pdf.SaveAs("embedImageBase64.pdf");

Ready to see what else you can do? Check out our tutorial page here: Additional Features