Toolbox101 All tools

Encoding

Decode Base32 back to text

Base32 Decode turns RFC 4648 Base32 strings back into the text they carry: NBUQ, with or without the = padding other encoders add, reads as hi. Lowercase input is read as uppercase, since the alphabet is case-insensitive, and spaces and line breaks are ignored. Developers use it to read tokens found in logs, check TOTP secrets and verify strings their own Base32 encoders produced. The bytes are read as UTF-8.

Open Base32 Decode in the app Browse all tools

How to use Base32 Decode

  1. Open Base32 Decode in the Toolbox101 app.
  2. Paste a Base32 string such as NBUQ or NBUQ==== into the Base32 box; case, spaces and padding do not matter.
  3. Read the decoded text in the Output box; it updates as you type.
  4. Click Copy to copy the result, or run it through Base32 Encode to confirm the round trip.

Worked example

Base32 Decode returns the output below for this input.

Input

NBUQ

Output

hi

Check it yourself: open Base32 Decode and enter the same input.

Frequently asked questions

Which characters are valid in a Base32 string?

The letters A–Z and the digits 2–7, 32 symbols in all. Case does not matter, and spaces, line breaks and = padding are skipped, so NBUQ and NBUQ==== decode the same. Any other character, such as 0, 1, 8 or 9, is reported as an error that names it.

Why does my decoded text show � characters or gibberish?

The Base32 may encode random bytes rather than readable text. A TOTP secret, for instance, is random bytes that rarely form printable characters, so decoding one gives symbols and � marks. The decoding is correct; the source just was not text.

Does the decoder handle lowercase Base32?

Yes. Input is read as uppercase before it is mapped onto the A–Z and 2–7 alphabet, so NBUQ, nbuq and mixed case all decode to the same text. Case-insensitivity is part of Base32's design.

How is Base32 decode different from Base64 decode?

Both recover the bytes an encoder packed, but the alphabets and bit grouping differ: Base32 maps five bits per symbol from 32 characters, Base64 maps six bits per symbol from 64. Base64 handles binary more compactly; Base32 output is longer but safe to read, type, and transmit in any context.

Use Base32 Decode now

Open Base32 Decode in the app

Runs in your browser. Nothing you type is uploaded.