Is final padding required?

No. The decoder accepts supported padded and unpadded groups. Some truncated inputs can still produce fewer bytes.

Base32 Decoder | Tool Factory

Tool workspace

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Input

Options

Alphabet

Remove non-alphabet chars

Your result appears here

Decode Base32 into bytes with a UTF-8 preview. Inspect five-bit symbol groups, emitted bytes, padding, and discarded characters.

This tool runs open-source code from CyberChef by GCHQ (Apache License 2.0). See open-source credits.

Each Base32 symbol contributes five bits. Complete eight-bit groups become output bytes.

The result includes decimal bytes, an optional UTF-8 preview, and a table of symbol calculations.

Inspect the raw bytes of a TOTP authenticator secret.

Sources: RFC 4648: Base32 alphabets and padding

Choose the alphabet and character handling

Paste the encoded value.
Use Alphabet A-Z2-7= for standard Base32 or 0-9A-V= for Base32hex.
Check Remove non-alphabet chars before decoding.

Decode Base32 symbols to bytes

Input: JBSWY3DPEHPK3PXP

Settings: Alphabet A-Z2-7=, Remove non-alphabet chars on

Result: [72, 101, 108, 108, 111, 33, 222, 173, 190, 239]

16 symbols carry 5 bits each, so 80 bits make 10 bytes. The first six bytes are the ASCII text Hello!. The last four bytes are not valid UTF-8, so the text preview shows a message; Preview Hex shows 48 65 6c 6c 6f 21 de ad be ef.

Invalid characters and incomplete groups

Removing non-alphabet characters can hide typing errors.
The alphabet is case-sensitive; convert lowercase input before decoding.
Base32 does not encrypt authenticator secrets.