Universal image decoder

Image Decoder – Detect, Preview & Download Images

Decode Base64 strings, data URLs, embedded code snippets or byte-array text into a detected image preview. Inspect the format, dimensions and file size, then download the decoded image locally.

Input

Paste Encoded Image Data

Auto detect

Paste raw Base64, a data:image URL, byte-array text, or a snippet from HTML, CSS, JSON, SVG, email or JavaScript. FileFlow Tool extracts the image payload and detects its format automatically.

Drop a .txt or .json file here. Your image data stays in this browser.

Up to 10 MB
Output

Decoded image preview

Waiting for input
Your decoded image will appear here

Paste encoded image data to detect the format, preview dimensions and file size before downloading.

Auto-detect formatMultiple input typesLocal preview
100% Private

Encoded image data is processed locally in your browser.

Instant Preview

Decode and inspect the image without waiting for an upload.

Format Detection

The tool identifies the decoded image MIME type automatically.

Developer Friendly

Paste Base64, data URLs and common code snippets.

Decoder guide

MIME types vs image file signatures

Image Decoder converts encoded image payloads into a visible preview. It accepts plain Base64, complete data URLs, and image data embedded in HTML, CSS, JSON, JavaScript, SVG, email and other text formats.

The decoder compares declared MIME information with decoded file signatures when possible, then displays the detected format, dimensions and file size before creating a local preview or download.

How to decode image data

  1. Paste encoded image data or choose a quick example.
  2. Select the matching input format when needed.
  3. Click “Decode Image Data”, review the preview and download the result.

Supported input patterns

  • Raw Base64 image strings and data:image URLs.
  • HTML img tags and CSS background-image values.
  • JSON, JavaScript, React, XML and email snippets.
  • Compatible byte-array text extracted from logs or APIs.

What the result includes

The result workspace shows the decoded preview, detected image type, dimensions, estimated file size, download action, reusable developer snippets and metadata-only conversion history.

Input formats

Choose the right image workflow

Base64 Decoder

Use the dedicated Base64 workflow for encoded image strings and data URLs.

Bytes to Image

Convert Uint8Array, Buffer, decimal bytes, hex or raw byte data into an image.

PNG Decoder

Validate and decode PNG-specific Base64 data while preserving transparency.

Common questions

Image Decoder FAQ

Is my encoded image uploaded?

No. Extraction, decoding, preview generation and download creation happen locally in your browser.

Which image formats can be previewed?

The decoder supports common formats such as PNG, JPG, JPEG, GIF, BMP, TIFF, SVG, WebP, AVIF and ICO when the browser can render the decoded result.

Can I paste HTML, CSS or JSON instead of plain Base64?

Yes. Choose the appropriate input format or paste the snippet directly. The decoder attempts to extract the embedded image data automatically.

What should I use for a decimal byte array or Uint8Array?

Use Bytes to Image for raw bytes. Image Decoder is optimized for Base64, data URLs and encoded image snippets.

Why can a valid Base64 string still fail?

The decoded bytes may not contain a supported image, the input may be truncated, or the browser may not support previewing that particular format.