Image to Base64

Convert an image to Base64 data URL.

Image

About Image to Base64 Converter

A Base64 data URI encodes the binary contents of an image as an ASCII string, prefixed with the MIME type (e.g., data:image/png;base64,...). This allows images to be embedded directly into HTML <img> tags, CSS background-image properties, JSON payloads, or JavaScript code without needing a separate image file on the server. For small images (under 10-20 KB), inline data URIs can reduce HTTP requests and improve page load performance. For larger images, external files with proper caching are more efficient. This tool reads your image using the browser's FileReader API and outputs the complete data URI string, ready to copy and paste. All processing is client-side — your image never leaves your device. For the reverse conversion, see our Base64 to Image tool, and for general Base64 encoding, use our Base64 Encoder.

How to Use Image to Base64 Converter

  1. Click Choose image and select an image from your device (JPEG, PNG, WebP, GIF, SVG, etc.).
  2. The tool instantly generates the Base64 data URI in the output area.
  3. Copy the complete data URI string for use in your HTML, CSS, or JavaScript code.
  4. Paste it as the src attribute of an <img> tag or as a url() value in CSS.

Key Features

  • Complete data URI — Outputs the full data URI string with correct MIME type prefix, ready for immediate use.
  • Universal format support — Works with JPEG, PNG, GIF, WebP, SVG, BMP, and any format the browser can read.
  • Instant conversion — The data URI is generated immediately after selecting the image.
  • One-click copy — Copy the entire data URI string to your clipboard with a single click.
  • 100% client-side — Your image is read using the FileReader API and never leaves your browser.
  • No size limit — Works with images of any size, though smaller images (under 20 KB) benefit most from inline embedding.

When to Use This Tool

  • Embedding small icons, logos, or UI graphics directly in HTML to eliminate extra HTTP requests.
  • Including images in CSS stylesheets as background images without external file dependencies.
  • Encoding images for use in JSON API payloads or database storage.
  • Creating self-contained HTML email templates with embedded graphics.
  • Generating data URIs for use in JavaScript canvas operations or dynamic image rendering.

Technical Details

The tool uses the JavaScript FileReader.readAsDataURL() method to read the selected image file and convert it to a Base64-encoded data URI. The output includes the MIME type prefix (e.g., data:image/png;base64,) followed by the Base64-encoded file contents. Base64 encoding increases the data size by approximately 33% compared to the original binary, so data URIs are most beneficial for small images where the overhead is offset by saving an HTTP request. For images larger than 20-30 KB, serving them as external files with proper cache headers is typically more efficient for web performance. The maximum data URI length varies by browser, but modern browsers support strings of several megabytes.

Conclusion

The Image to Base64 Converter is a fast, private tool for generating data URIs from any image file. By embedding small images inline, you can reduce HTTP requests and simplify asset management — all processed entirely in your browser with no server upload required.

Frequently Asked Questions

Is my image uploaded to a server?
No. The image is read entirely in your browser using the FileReader API. Nothing is sent to any server, ensuring complete privacy for all your files.
What is a data URI?
A data URI (e.g., data:image/png;base64,…) is a string that contains the file content encoded in Base64. You can use it directly as an <img src> value, in CSS background-image: url(), or in JavaScript and APIs.
What image formats are supported?
Any format the browser can decode: JPEG, PNG, GIF, WebP, SVG, BMP, and more. The output data URI will include the correct MIME type for the original format.
Should I use Base64 data URIs for all images?
No. Data URIs are best for small images (under 10-20 KB) where eliminating an HTTP request outweighs the ~33% size increase from Base64 encoding. For larger images, external files with proper caching are more efficient for web performance.