Image to Base64 Converter Online — Free Tool
Encode any image file into a Base64 data URL string for seamless embedding into HTML or CSS files.
About this tool
Base64 data URLs embed images directly in HTML, CSS, or JSON without separate asset files. This tool encodes an image file to a Base64 string you can paste into code or configs.
Useful for small icons, email templates, and prototypes—large images produce very long strings and are better served as files.
Common use cases
- Inlining small icons in HTML or CSS
- Embedding images in JSON API fixtures
- Testing data-URI support in email clients
- Sharing a single self-contained HTML demo
How to use
- Select an image file from your device.
- Wait for Base64 encoding to complete locally.
- Copy the data URL or raw Base64 string.
- Paste into your stylesheet, markup, or API payload.
This page is available at /tools/image-to-base64/.
Understanding the result
- Data URLs start with data:image/...;base64, followed by the encoded payload.
- Encoded size is roughly 33% larger than the binary file.
- Very large images bloat HTML and hurt performance—prefer URLs for big assets.
- MIME type in the prefix should match the source format (png, jpeg, webp).
Related tools
FAQ
What is a data URL?
A URI scheme that embeds file content inline: data:[mediatype];base64,[data]. Browsers load it like a normal image src.
Is there a size limit?
Browser and editor limits apply. Keep inlined images small (often under 10–20 KB).
Can I decode Base64 back to an image?
Yes. Paste the data URL in a browser address bar or use a Base64 decoder tool.
Is my image uploaded?
No. Encoding happens entirely in your browser.