Is this tool free to use?

Yes, this tool is 100% free with no hidden charges, no sign-up required, and no usage limits. All features are accessible to everyone for both personal and commercial use.

Is my data uploaded to any server?

No. This tool processes everything entirely in your browser using client-side JavaScript. Your data never leaves your device, is never uploaded to any server, and is not stored or logged. This ensures complete privacy.

Can I use this tool offline?

Yes. Once the page is loaded, this tool works offline without any internet connection. Everything runs locally: Filename and other values are processed on your device, never sent to a server.

Does this tool work on mobile devices?

Yes. This tool is fully responsive and works on all devices including smartphones, tablets, and desktop computers. No app installation is needed.

How does the Base64 To File protect my privacy?

All processing happens in your browser with no server uploads. Your data never leaves your device.

Free Online Base64 to File Decoder

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Updated: 2026-07-11

Paste Base64 String

Base64 encoded string (with or without data URI prefix):

File type (if not auto-detected): Filename:

Decoded File Preview

About Base64 to File Decoder

This free online Base64 to File decoder converts Base64 encoded strings back into their original binary files. Whether you need to extract an image from a CSS data URI, decode a Base64-encoded PDF, or convert any Base64-decode any binary data, this tool handles it all — entirely in your browser.

Common Use Cases

Extract images from data URIs: Decode Base64 images embedded in HTML, CSS, or JSON
API response decoding: Convert Base64-encoded file data from API responses back to downloadable files
Email attachment extraction: Decode Base64-encoded email attachments
Debug Base64 data: Preview and verify Base64-encoded content before using it

Why choose Base64 to File Decoder

Auto-detect MIME type: Automatically identifies file type from data URI prefix
Preview support: Images are previewed inline; other files show type and size info
100% Client-Side: No data is sent to any server — your data stays private
Any file type: Supports images, PDFs, audio, video, fonts, and any binary data
One-click download: Download the decoded file with the correct extension

Frequently Asked Questions

What's the difference between raw Base64 and data URI?

A data URI includes a prefix like data:image/png;base64, followed by the Base64 string. Raw Base64 is just the encoded data without any prefix. This tool handles both formats — it auto-detects the data URI prefix and extracts the MIME type, or you can manually specify the file type for raw Base64 strings.

Can I decode multiple Base64 strings at once?

Currently, the tool processes one Base64 string at a time. For multiple files, simply paste each string and decode it, then download the result before moving to the next one.

Is my data secure?

Yes. All decoding happens locally in your browser using the built-in atob() function and Blob API. Your Base64 data is never transmitted to any server. This makes the tool safe for decoding sensitive data like API keys, certificates, or private documents.

Why does my decoded file look corrupted?

This usually happens when the Base64 string is incomplete or contains invalid characters. Make sure you've copied the entire Base64 string without truncation. Also verify that the MIME type is correct — a PNG decoded as JPEG will appear corrupted.

What's the maximum Base64 string size?

The limit depends on your browser and device memory. Most browsers handle Base64 strings up to 50MB (decoding to ~37MB files). For very large files, you may experience browser slowdowns or out-of-memory errors.