Uudecode Decoder

Summary

Paste a UUencoded block and instantly recover the original text or binary content in your browser.

How it works

1. Paste your UUencoded text into the input field (include the "begin" header and "end" footer if present).
2. Click "Decode" to run the decoding algorithm client-side in your browser.
3. Each encoded line is parsed: the first character gives the byte count, and the remaining characters are converted back to 6-bit groups.
4. The recovered bytes are assembled and displayed as decoded text.
5. If the original data was binary, click "Download File" to save the exact binary output.
6. Filename and permission mode shown in the "begin" line are extracted and displayed automatically.

Use cases

• Recover the original content from legacy email attachments using UUencoding.
• Decode UUencoded Usenet binary posts archived from the early internet.
• Verify that your UUencoder produces output that round-trips correctly.
• Debug shell scripts that use uuencode/uudecode to embed binary payloads.
• Inspect UUencoded configuration blobs embedded in older Unix tools.
• Learn the UUencoding algorithm by comparing encoded input with decoded output.

Frequently Asked Questions