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TextArray1.41.0
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UUencode / UUdecode

Convert text or binary data to a uuencoded ASCII block, or decode one back.

Input
Output
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UUencode / UUdecode
UUencode converts arbitrary bytes into plain ASCII text wrapped in a "begin" header and an "end" footer — the format Unix mail and Usenet clients used for decades to attach binary files to text-only messages. This tool encodes any text you paste into that format, or decodes an existing uuencoded block back to its original content, entirely in your browser.
When encoding, set the file name and permissions that appear on the "begin" line, and the number of bytes per line — the format allows up to 45, the classic default. Turn on the xxencode option to use its alternative, case-insensitive-safe alphabet instead of the standard one; some old transports and BBS systems expected xxencode rather than uuencode, and the two are not interchangeable. When decoding, the tool scans the pasted text for a "begin" line even if it is surrounded by other content, such as an email body or a log excerpt, and reads data lines until it reaches "end" or a zero-length marker line.
Decoding is strict by default: a line that cannot be parsed is reported by its number so you can find and fix it in the source, and a block missing its "end" footer is flagged rather than silently truncated. Turn on "Allow missing end footer" if you are decoding a block that was cut off before the footer was captured. The tally under the output reports bytes in, bytes out and, on decode, the file name recovered from the header.
Everything runs locally — your text or file content is never uploaded to a server. Copy the result, download it as a .txt file, or send the output straight back into the input to decode what you just encoded and confirm a round trip.
FAQ
What is uuencode used for today?
Mostly for compatibility: reading old email attachments, Usenet archives, BBS file transfers or embedded blocks in legacy scripts and firmware images that still use the format.
What's the difference between uuencode and xxencode?
Both pack 3 bytes into 4 printable characters the same way. Uuencode starts its alphabet at the space character (with a backtick standing in for zero); xxencode uses a fixed set of digits and letters instead, which survives some mail gateways that mangle characters outside that range.
Why does decoding fail on my pasted block?
Each data line starts with a character that declares how many bytes it carries — if a line was wrapped, trimmed or had characters altered in transit, that count no longer matches the data and decoding stops there. The error names the exact line number so you can compare it against the original.
Can I decode a block that is missing its "end" line?
Yes, turn on "Allow missing end footer". By default the tool flags a missing footer as a likely sign the block was cut off, but the option decodes whatever data lines are present anyway.
Is my data uploaded anywhere?
No. Encoding and decoding run entirely in your browser — nothing you paste here is sent to a server.