Which variant should I pick?

If the string is uppercase letters and digits 2–7, it is Base32. If it is mixed case with no 0, O, I or l, it is almost certainly Base58. If it contains punctuation like or a dense mix of symbols, it is ASCII85/Base85.

Why does Base58 have no check digit here?

Plain Base58 is just an alphabet. Base58Check — used by Bitcoin addresses — appends a 4-byte checksum, which shows up as extra trailing bytes when you decode it here.

Is Base32 case sensitive?

No. RFC 4648 Base32 is defined over uppercase A–Z, and lowercase input is folded automatically, which is why it is popular for anything a person might type by hand.

Base32 / Base58 / Base85 Decoder

Decode Base32, Base58 and ASCII85/Base85 strings — pick the alphabet and read the bytes.

live · client-sideData, Radix & Stringfree · no sign-up

RAW INPUT

Variant

DECODED

Output appears here as you type — decoded on your device.

Input is processed on your device. Nothing you paste is sent anywhere.

What is the Base32 / Base58 / Base85 Decoder?

Base32, Base58 and Base85 are alternative binary-to-text encodings to Base64, each trading density for a different property: Base32 for case-insensitive readability, Base58 for human-transcribable identifiers, and Base85 for compactness.

Base32 (RFC 4648) uses 32 characters — A–Z and 2–7 — so it survives case folding, is easy to read aloud and is the encoding behind TOTP secrets, onion addresses and many file-sharing hashes. It costs about 60% overhead compared with raw bytes.

Base58 drops the visually ambiguous characters (0, O, I and l) and any punctuation, which is why Bitcoin addresses, IPFS CIDs and Flickr short URLs use it: a human can copy one off a screen without mistaking a zero for an O. Base85/ASCII85 goes the other way, packing 4 bytes into 5 characters for only 25% overhead — you'll meet it inside PDF streams and Git binary patches.

Choose the variant in the Variant selector and the decoder applies the matching alphabet, validates the characters and returns the decoded bytes with a text and hex view.

Base32 / Base58 / Base85 Decoder at a glance

Base32: RFC 4648 · A–Z 2–7 · +60% size
Base58: Bitcoin alphabet · no 0 O I l · +37% size
Base85: ASCII85 · 5 chars per 4 bytes · +25% size
Case sensitive: Base32 no · Base58 and Base85 yes

How to use the Base32 / Base58 / Base85 Decoder

1Choose the encoding you have: Base32, Base58 or Base85/ASCII85.
2Paste the encoded string — whitespace and line wrapping are ignored.
3Read the decoded text and byte view, then copy the output.

When you would reach for it

Decoding a Base32 TOTP/2FA secret to check what a authenticator app was given.
Inspecting a Base58 Bitcoin address or IPFS content identifier byte by byte.
Unpacking an ASCII85 stream lifted out of a PDF or a Git binary diff.

Base32 / Base58 / Base85 Decoder — frequently asked questions

Last reviewed 25 July 2026 · questions or corrections: contact@decoder.tools