Base32 encodes binary data using a 32-character alphabet (A–Z plus 2–7) with padding to a multiple of 8 characters. It is used in TOTP authenticator secrets (Google Authenticator, Authy), DNS labels, and some checksums because it avoids ambiguous characters like 0/O and 1/I/l.

Does my data leave my device?

No. The Base32 encoding and decoding is implemented in pure JavaScript and runs entirely in your browser.

Does it work on mobile?

Yes. The tool works in any modern mobile browser and is optimised for touch use.

Base32 Encoder / Decoder — RFC 4648 Online Tool

Base32 Encoder / Decoder

Encode text to Base32 (RFC 4648) or decode Base32 back to plain text.

100% client-side · no upload

Input

Output

What is Base32?

Base32 encodes binary data using 32 characters: uppercase A–Z and digits 2–7. Padding characters (=) are added to make the output a multiple of 8 characters. Compared to Base64, Base32 avoids case sensitivity and ambiguous characters, making it suitable for DNS, human-readable tokens, and TOTP authenticator secrets.

How to use

Paste your text into the input box.
Click Encode → Base32 to encode, or Decode ← Base32 to decode.
Copy the result with the Copy button.

常見問題

What is Base32?: Base32 encodes binary data using a 32-character alphabet (A–Z plus 2–7) with padding to a multiple of 8 characters. It is used in TOTP authenticator secrets (Google Authenticator, Authy), DNS labels, and some checksums because it avoids ambiguous characters like 0/O and 1/I/l.
Does my data leave my device?: No. The Base32 encoding and decoding is implemented in pure JavaScript and runs entirely in your browser.
Does it work on mobile?: Yes. The tool works in any modern mobile browser and is optimised for touch use.