Content and text
Base64 Decoder
Decode Base64 or URL-safe Base64 back to readable text, Arabic included.
Runs in your browser; nothing is uploaded. · Free, no account · 1 min
Line breaks and a data: URI prefix are ignored.
Importing a saved run into your account is coming soon. Until then, your last runs stay in this browser only, and you can download your files.
How to use
- Paste the Base64 text, with or without line breaks or a data: prefix.
- Read the notes: invalid characters, missing padding and URL-safe alphabet.
- If the bytes are not text, check the hex preview to see what the data is.
- Copy the decoded text or download it.
What it checks and how it works
The decoder accepts both alphabets of RFC 4648: the standard one (+ and /) and the URL-safe one (- and _). It ignores whitespace and a data: URI prefix, adds missing = padding, and reports any character outside the alphabet with its position. The bytes are then read as UTF-8 (RFC 3629), so Arabic text comes back correctly.
If the bytes are not valid UTF-8, the data is probably an image, a file or another encoding, and the tool shows the start of the data in hex instead of garbled text. It cannot tell you what the data was meant to be, and a decoded value may still be sensitive, so treat it with care.
Sources
- RFC 4648: The Base16, Base32, and Base64 Data Encodings opened 29 Oct 2026
- RFC 3629: UTF-8, a transformation format of ISO 10646 opened 29 Oct 2026
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Questions
About this tool
The text was probably encoded in another character set, not UTF-8. The tool tells you when the bytes are not valid UTF-8 and shows them in hex.
Base64 text should end with = to fill the last group of four characters. Many systems drop it, and the tool restores it before decoding.
You can decode each of its dot-separated parts, which are Base64URL text. That shows the contents but does not check the signature.
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