Base64 Image Preview
Paste a Base64 string or data URI to instantly preview the decoded image. Shows MIME type, dimensions, and file size.
What Is Base64 Image Preview?
Base64 Image Preview decodes a Base64-encoded image string or data URI and displays it as a real image — right in your browser. It also reveals the MIME type, pixel dimensions, and decoded file size. Useful for debugging CSS background-image values, email template inline images, API payloads, and any context where an image is embedded as text.
How to Use
- Paste a Base64 string or a full
data:image/...;base64,...URI into the input - Click Preview — the image renders immediately if the data is valid
- Check the info panel for MIME type, dimensions, and file size
- Click Download to save the decoded image file
- Use Copy data URI to grab the full
data:string for CSS or HTML
Features
- Supports PNG, JPEG, GIF, WebP, BMP, ICO, SVG and any Base64 image data
- Auto-detects MIME type from magic bytes when not present in the data URI
- Displays image dimensions (width × height in pixels)
- Shows decoded byte size with human-readable formatting
- Download the decoded image to your device
- 100% client-side — image data never leaves your browser
Frequently Asked Questions
Can I paste a full data URI?
Yes. Both raw Base64 (no prefix) and full data:image/png;base64,... data URIs are accepted. The tool strips the prefix automatically.
Why does "Invalid Base64" appear?
The string contains characters outside the Base64 alphabet or incorrect padding. Make sure you copied the full string — partial pastes are a common cause.
How do I encode an image to Base64?
Use the Image to Base64 tool on this site to upload an image and get its Base64 representation, which you can then paste back here to verify.
Is there a size limit?
There is no hard limit — the browser handles the decoding. Very large images (50 MB+) may cause the browser tab to slow down temporarily.