Base32 Encoder & Decoder — RFC 4648, TOTP-Compatible
Encode and decode Base32 strings online (RFC 4648). Handles TOTP / Google Authenticator secrets, DNSSEC records, and other case-insensitive binary-to-text formats. 100% local.
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CommentsFrequently Asked Questions
What is the difference between Base32 and Base64?
Base32 uses 32 case-insensitive characters (A–Z + 2–7), each carrying 5 bits, while Base64 uses 64 characters (6 bits each). Base32 output is about 25% longer than Base64 but is easier for humans to read out loud, transcribe, or type — which is why TOTP secrets and DNSSEC records use it.
Why does my TOTP / Google Authenticator secret use Base32?
TOTP (RFC 6238) mandates Base32 for the shared secret because the secret is often transferred by scanning a QR code that also encodes a human-typeable fallback string. Base32's case-insensitive, 0/1/8/9-free alphabet minimises transcription errors.
What is the 'hex' variant?
Base32hex (also RFC 4648) uses 0–9 + A–V instead of A–Z + 2–7, so that the natural sort order matches the underlying byte order. It shows up mainly in DNSSEC NSEC3 records; regular Base32 is much more common everywhere else.
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