How to Draw Text & Bitmap on PDFs using C#

Understanding Coordinate System

Before drawing text, understand the PDF coordinate system. The origin (0,0) is located at the bottom-left corner of the page, with X values increasing to the right and Y values increasing upward. This differs from many graphics systems where the origin is at the top-left.

:path=/static-assets/pdf/content-code-examples/how-to/draw-text-and-bitmap-draw-text.cs

using IronPdf;
using IronSoftware.Drawing;

ChromePdfRenderer renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderHtmlAsPdf("<h1>testing</h1>");

// Draw text on PDF
pdf.DrawText("Some text", FontTypes.TimesNewRoman.Name, FontSize: 12, PageIndex: 0, X: 100, Y: 100, Color.Black, Rotation: 0);

pdf.SaveAs("drawText.pdf");

What Fonts Can I Use?

The DrawText method currently supports all Standard Fonts in IronPDF, including Courier, Arial (or Helvetica), TimesNewRoman, Symbol, and ZapfDingbats. Visit the 'Standard Fonts in IronPDF' section in the Manage Fonts article for italic, bold, and oblique variants of these font types.

The ZapfDingbats font can display symbols such as ▲. For a comprehensive list of supported symbols, visit Wikipedia on Zapf Dingbats.

Output fonts sample on PDF

How Can I Add Text with Line Breaks?

The draw text action supports newline characters, allowing you to render text with built-in newlines for better formatting and visual clarity. This is useful when adding multi-line annotations or creating structured text layouts.

To achieve this, add newline characters (\n) to the text string. Using the example above:

// Multi-line text example with proper spacing
string textWithNewlines = "Some text\nSecond line\nThird line with more content";
pdfDoc.DrawText(textWithNewlines, font, position);

// You can also use Environment.NewLine for platform-specific line breaks
string platformText = $"Line 1{Environment.NewLine}Line 2{Environment.NewLine}Line 3";
pdfDoc.DrawText(platformText, font, position);

// Multi-line text example with proper spacing
string textWithNewlines = "Some text\nSecond line\nThird line with more content";
pdfDoc.DrawText(textWithNewlines, font, position);

// You can also use Environment.NewLine for platform-specific line breaks
string platformText = $"Line 1{Environment.NewLine}Line 2{Environment.NewLine}Line 3";
pdfDoc.DrawText(platformText, font, position);

How Do I Use Custom Fonts?

Custom fonts are supported with the DrawText method, expanding your typography options beyond standard fonts. This feature is essential when maintaining brand consistency or working with specialized fonts. For advanced font management, see our guide on managing fonts in PDFs.

Below is an example with the Pixelify Sans Font added for the text:

:path=/static-assets/pdf/content-code-examples/how-to/draw-text-and-bitmap-draw-custom-font.cs

using IronPdf;
using IronSoftware.Drawing;
using System.IO;

ChromePdfRenderer renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderHtmlAsPdf("<h1>testing</h1>");

// Add custom font to the PDF
byte[] fontByte = File.ReadAllBytes(@".\PixelifySans-VariableFont_wght.ttf");
var addedFont = pdf.Fonts.Add(fontByte);

// Draw text on PDF
pdf.DrawText("Iron Software", addedFont.Name, FontSize: 12, PageIndex: 0, X: 100, Y: 600, Color.Black, Rotation: 0);

pdf.SaveAs("drawCustomFont.pdf");

Advanced Text Positioning

When positioning text precisely, consider these tips:

• Page Dimensions: Use pdf.Pages[pageIndex].Width and pdf.Pages[pageIndex].Height to get page dimensions
• Rotation: The rotation parameter accepts degrees (0-360) for angled text
• Color Options: Beyond basic colors, use RGB values: Color.FromArgb(255, 100, 100)

IronPDF's DrawBitmap method enables you to add bitmaps to existing PDF documents. This method functions similarly to the Image Stamper feature, allowing you to stamp images onto existing PDFs. For complex image manipulation needs, explore our guide on adding images to PDFs.

Sample image

What Does the Implementation Look Like?

:path=/static-assets/pdf/content-code-examples/how-to/draw-text-and-bitmap-draw-bitmap.cs

using IronPdf;
using IronSoftware.Drawing;

ChromePdfRenderer renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderHtmlAsPdf("<h1>testing</h1>");

// Open the image from file
AnyBitmap bitmap = AnyBitmap.FromFile("ironSoftware.png");

// Draw the bitmp on PDF
pdf.DrawBitmap(bitmap, 0, 50, 250, 500, 300);

pdf.SaveAs("drawImage.pdf");

Output PDF

What Additional Parameters Are Available?

• PixelFormat: The PixelFormat property specifies the color data format for the bitmap, primarily controlling transparency support. The default value is Format32bppArgb. Choose between pixel enum formats Format32bppRgb and Format32bppArgb by passing the parameter as an option. This is useful when working with background and foreground elements in PDFs.

• IgnorePageRotation: This bool property determines whether the method ignores page rotation when drawing the bitmap. By default, the value is false. Especially useful when applying watermarks consistently to all pages, regardless of rotation.

Common Use Cases and Best Practices

When drawing text and images on PDFs, consider these practical applications:

1. Dynamic Watermarking: Add company logos or "CONFIDENTIAL" stamps to sensitive documents
2. Page Numbering: Draw page numbers in consistent positions across all pages
3. Signature Placement: Add signature images at designated locations on forms
4. Header/Footer Enhancement: Complement existing headers with dynamic content

For debugging and monitoring PDF operations, implement custom logging to track drawing operations and ensure proper execution.

Performance Considerations

When working with multiple pages or large documents:

• Batch operations when possible to minimize memory usage
• Dispose of bitmap objects after use to free resources
• Consider pre-loading frequently used images to improve performance

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