Online Tool Store
Base32 Encoder Decoder
Encode text to RFC 4648 Base32 or decode a Base32 string back, with padding and alphabet options, entirely in your browser.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Data Converters
Base32 Encoder Decoder
Frontend preview — no upload or external service.
Base32 output
Example: "otpauth" encodes to N5XWEZDPMFXGG=== using the RFC 4648 alphabet with padding kept.
How the Base32 Encoder Decoder works
- Paste the text or Base32 string you want to convert.
- Pick a direction and the alphabet your source system uses.
- Read the converted value from the result panel and copy it out.
The method
Base32 reads the input five bits at a time and maps each group to one of 32 characters, so every 5 bytes become exactly 8 output characters.
8 output chars = ceil(bytes / 5) x 8, padded with '=' to a multiple of 8
5 bytes encode cleanly; 1 leftover byte produces 2 characters plus 6 padding signs.
FAQ
Why does Base32 skip 0, 1 and 8?
The RFC 4648 alphabet is A-Z plus 2-7 precisely so no character can be mistaken for another when a value is read aloud or typed by hand: zero against O, one against I, eight against B.
Is Base32 encryption?
No. It is a reversible encoding meant to move binary safely through text-only channels. Anyone can decode it, so never treat a Base32 string as a secret in itself.
Why is Base32 used for 2FA secrets?
Authenticator enrolment URIs carry the shared secret as Base32 because it survives case-insensitive systems and manual typing far better than Base64.
How we compare
| Feature | Online Tool Store | A spreadsheet | A desktop converter |
|---|---|---|---|
| Case-insensitive input | ✓ | ✗ | Depends |
| base32hex and Crockford alphabets | ✓ | ✗ | ✗ |
| Nothing leaves the page | ✓ | ✓ | ✗ |
| No install step | ✓ | ✗ | ✓ |
The Base32 Encoder Decoder covers the alphabets that trip people up — 2FA secrets, base32hex sort keys, Crockford IDs — without a terminal or an upload.