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Drop image here or click to upload

Supports JPG, PNG, WEBP, GIF — Max 20 MB

Base64 Length

Base64 Output (data URI):

Use in HTML: <img src="[paste here]">

Use in CSS: background-image: url([paste here]);

What is Base64 Image Encoding?

Base64 encoding converts binary image data into ASCII text characters. The resulting string (called a "data URI") can be embedded directly in HTML, CSS, or JSON without requiring a separate HTTP request for the image.

When to Use Base64 Images

  • Small icons and images (under 5 KB) — eliminates HTTP request overhead
  • Email HTML — some email clients block external images
  • Single-file web pages — embed all assets in one HTML file
  • JSON data — store images in API responses or configuration files
  • CSS sprites — embed small background images in your stylesheet

When NOT to Use Base64

Avoid Base64 for large images because encoding increases size by ~33% and prevents browser caching of the image separately from the page.

Frequently Asked Questions

Why is the Base64 string so long?

Base64 encoding increases data size by approximately 33% compared to the original binary. A 100 KB image becomes ~133 KB as a Base64 string.

How do I use the Base64 output in HTML?

Copy the entire string (including the "data:image/..." prefix) and use it as the src attribute: <img src="data:image/jpeg;base64,/9j/4AAQ...">