Base58 Decode
Decode Base58 strings back to bytes and text.
Decode Base58 (Bitcoin alphabet) back to text. Free, offline, runs in your browser. Read more Show less
What is Base58 decoding?
Base58 decoding reverses the Base58 encoding, turning a string like Cn8eVZg back into the original bytes. The alphabet is the Bitcoin standard. Leading 1 characters decode to leading zero bytes.
The decoder here is strict: it rejects any character not in the alphabet, and any string that does not produce a whole number of bytes. This catches typos before they silently produce garbage.
How to use
Paste Base58 into the input box. The result is the original text if the bytes decode to valid UTF-8, or the raw bytes shown as-is if they do not. Whitespace is ignored.
Base58Check and checksums
Most real-world Base58 strings use Base58Check, which prepends a version byte and appends a 4-byte double-SHA-256 checksum. This tool decodes raw Base58 only and does not verify checksums.
To decode a Bitcoin address fully, decode with this tool, split off the last 4 bytes as the checksum, hash the first bytes twice with SHA-256, and compare. The SHA-256 tool can help.
FAQ
Why does decoding fail?
The input contains a character that is not in the Bitcoin alphabet. Common mistakes include pasting a string with the digit 0 instead of lowercase o, or uppercase O instead of zero. The error message tells you which character is wrong.
Does it accept all Bitcoin addresses?
Yes. Bitcoin legacy addresses starting with 1 or 3 are Base58Check-encoded and will decode. You still need to verify the checksum yourself if you want to be sure the address is valid.
What about Bech32 addresses?
Newer Bitcoin addresses starting with bc1 use Bech32, not Base58. This tool does not handle Bech32.
Is my data sent anywhere?
No. Decoding is entirely local.