Base64 Decoder
Decode Base64 back to readable text, standard or URL-safe.
Base64 Decoder
Developer tool running locally in browser
What does Base64 Decoder do?
Decode Base64 strings back to text with UTF-8 decoding, accepting both the standard and URL-safe alphabets and tolerating missing padding. Invalid input is diagnosed rather than silently producing gibberish.
How to Use Base64 Decoder
- 1Paste the Base64 stringPadding and line breaks are optional.
- 2Read the decoded textIt appears immediately.
- 3Copy the resultOr switch to hex view for binary data.
Key Features
- Handles standard and URL-safe alphabets automatically
- Missing padding added automatically
- Whitespace and line breaks ignored
- Detects binary content and offers a hex view instead of garbled text
- Clear diagnosis when the input is not valid Base64
Frequently Asked Questions
Why does my Base64 fail to decode?
Usually truncation, or characters outside the alphabet sneaking in during a copy. Base64 must be a multiple of four characters once padded; the tool pads for you but cannot recover missing data.
Why is the output unreadable?
Because the data was not text. Base64 frequently encodes images, compressed archives or encrypted payloads. Switch to hex view — the first few bytes usually identify the format.
Can I decode a JWT with this?
You can decode each segment individually, but the JWT decoder is easier — it splits the token, decodes header and payload together, and interprets the standard claims.
Is my input sent to a server?
No. Decoding uses the browser’s built-in function, so tokens and payloads never leave the page.
Input is processed in your browser and never transmitted. That said, treat any web page as untrusted for live production secrets — rotate anything you paste anywhere.
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