What happens if the input is not valid Base64?

The tool will display a clear error message indicating that the input is not a valid Base64 string. It will not produce garbled output.

Can I decode Base64 that contains Unicode?

Yes. The decoder correctly handles UTF-8 encoded Base64 strings, including accented characters, CJK scripts, and emoji.

What is the maximum input size?

There is no hard limit, but very large strings (over a few MB) may cause your browser to slow down since decoding happens in the main thread.

Base64 Decode

Decode Base64 strings to plain text. Instantly reveals content from API responses and encoded configurations. Handles UTF-8 encoded content including Unicode characters. Invalid Base64 input is caught gracefully with a clear error message. Runs entirely in your browser.

Your files are processed entirely in your browser. Nothing is uploaded to any server.

How to Use Base64 Decode

1
Paste or type your text
Enter your text in the input area. You can paste from clipboard or type directly.
2
See instant results
The tool processes your text automatically as you type. Adjust options if available.
3
Copy the output
Click the copy button to save the result to your clipboard. No data leaves your browser.

Frequently Asked Questions

Next Steps

Re-encode if needed

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