Base64 to Image Decoder — Preview & Download Online
Paste any Base64 string or Data URI to instantly preview the decoded image in your browser. Detects JPEG, PNG, GIF, WebP, SVG, and BMP automatically. Zoom in to inspect detail, then download the image file. Free, private, no signup.
How to Convert Base64 to an Image Online
- Paste your Base64 string or full Data URI (starting with
data:image/...) into the input area. - The image renders instantly in the preview panel. The MIME type, estimated file size, and pixel dimensions appear in the info bar.
- Use the Zoom slider to scale the preview from 50% to 200% for close inspection. Click Reset to return to 100%.
- Click Download Image to save the file with the correct extension (e.g. decoded-image.png).
- Click Copy Data URI to copy the full data URI to your clipboard for use in HTML or CSS.
Key Features
- Accepts raw Base64 strings and full Data URIs with MIME prefix
- Auto-detects image format from magic bytes — JPEG, PNG, GIF, WebP, BMP, ICO, SVG
- Instant browser rendering — no server round-trip required
- Zoom slider from 50% to 200% for detailed image inspection
- MIME type, estimated file size, and natural pixel dimensions displayed
- Download with correct file extension based on detected format
- Copy Data URI button for embedding in HTML or CSS
- Checkerboard background to reveal image transparency
Base64 to Image Use Cases
Verifying Base64-encoded images in API responses
REST APIs sometimes return profile pictures, generated charts, or QR codes as Base64-encoded strings. Paste the value here to immediately confirm the image decoded correctly before writing any code to handle it.
Extracting images from HTML or CSS source code
When auditing a webpage's source, you may find large Data URIs embedded in img tags or CSS background-image properties. Paste the Base64 portion here to preview the image and download it as a standalone file.
Debugging email template images
HTML email templates often embed images as Base64 Data URIs. If an embedded image is not rendering correctly, paste the Base64 here to check whether the string is valid and the image data is intact.
Converting Base64 to downloadable PNG or JPEG files
If you have a Base64 string from a canvas.toDataURL() call, a database BLOB field, or a JSON payload and need the actual image file, paste the string here and click Download to save the decoded binary to disk.
FAQ's
The tool inspects the first characters of the Base64 string to detect known image format signatures (JPEG: /9j/, PNG: iVBORw0KGgo, GIF: R0lGOD, WebP: UklGRg) and automatically prepends the correct Data URI prefix. If the format cannot be identified, it defaults to image/png and attempts to render.
The zoom slider applies a CSS scale transform to the preview image from 50% to 200% of its natural size. This only affects what you see — the underlying data URI and downloaded file are unchanged.
The tool generates a filename based on the detected MIME type — for example, decoded-image.jpg for JPEG, decoded-image.png for PNG, decoded-image.webp for WebP, and so on.
Estimated size = Base64 string length × 0.75, accounting for the 4:3 Base64 character to binary byte ratio. The actual decoded size may differ by a few bytes due to padding characters.
This tool is specifically designed for image decoding — it renders the result as an image in the browser. For decoding arbitrary text or binary Base64 data, use the Base64 Encoder/Decoder tool instead.
The auto-detect handles JPEG, PNG, GIF, WebP, BMP, ICO, and SVG by checking known Base64 magic byte signatures. Any format your browser can render natively will also work when provided as a complete Data URI with the correct MIME type.
No. The Base64 string is decoded and rendered entirely in your browser. No data is transmitted to any external server. The tool works offline once the page has loaded.