Decode Ascii85 or base85 data back to bytes, accepting the Adobe delimiters and the z shortcut that stands for four zero bytes.
Show calculation steps
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How to use the Ascii85 Decoder
- Paste the Ascii85 data, with or without the surrounding delimiters.
- Keep the binary option on "Hex dump" for PDF stream data, which is rarely readable text.
- Click "Decode Ascii85".
Frequently asked questions
Do I need to strip the delimiters first?
No. The opening and closing markers used by Adobe are recognised and removed automatically, so you can paste a stream exactly as it appears in a PDF.
What causes a "group decodes above 2 to the 32" error?
Each five-character group must represent a 32-bit value. If the digits decode to something larger, the group is invalid – normally the sign of corrupted data, or of text that is not really Ascii85.
Why does the last group behave differently?
A final partial group is padded internally and then trimmed back, so that the byte count matches the original data exactly. A trailing group of only one character is impossible in valid Ascii85 and is reported as truncation.
