Base32 Encoder & Decoder

Convert text to and from Base32 (RFC 4648). Everything runs locally in your browser, so your data is never uploaded.

100% client-side · nothing is uploaded

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Quick answer

Base32 is a free, private online tool that lets you encode text to Base32 or decode a Base32 string back to text (RFC 4648). It runs entirely in your browser, so nothing you enter is uploaded to a server.

How to use the Base32

Choose the mode you need with the Encode / Decode toggle at the top of the tool.
Type or paste your text into the Input box — the result appears instantly as you type.
Use Swap (⇅) to move the output back into the input and flip the mode, which is handy for round-trips.
Click Copy to copy the result, or Clear to start over.

Privacy: this tool runs entirely in your browser. Your input is never sent to, received by, or stored on any server — there are no uploads and no tracking of what you enter.

About Base32

What is Base32?

Base32 encodes binary data using 32 characters: the uppercase letters A–Z and digits 2–7. It is case-insensitive and avoids easily-confused characters, which makes it handy for things people read or type, like TOTP secrets and some file systems.

How it differs from Base64

Base32 groups data into 5-bit chunks instead of 6-bit, so it produces longer output (about 60% larger than the input) but with a smaller, more robust alphabet. Padding uses the = character to a multiple of 8 characters.

Common uses

Two-factor authentication secrets (TOTP/HOTP), Bitcoin/Bech32-style encodings, DNS, and any context where output must survive case-insensitive systems.

Frequently asked questions

Is Base32 the same as Base64?

No. Base32 uses a 32-character set and produces longer output, but it's case-insensitive and easier to read aloud or type.

Does it support Unicode?

Yes — text is encoded as UTF-8 first, so any character round-trips correctly.

Why is my output padded with =?

Base32 pads to a multiple of 8 characters with =, just as Base64 pads to a multiple of 4.

Understanding Base32 in depth

What Base32 is

Base32 is a binary-to-text encoding that represents data using 32 characters: the uppercase letters A–Z and the digits 2–7 (defined in RFC 4648). Like Base64 it lets arbitrary bytes travel safely through text-only systems, but it trades efficiency for robustness — the smaller, case-insensitive alphabet is easier for humans to read aloud, type, and transcribe without errors.

How the encoding works

Where Base64 packs data into 6-bit groups, Base32 uses 5-bit groups. Input bytes are read as a continuous stream of bits and sliced into chunks of five, each chunk mapping to one of the 32 characters. Because 5 and 8 do not divide evenly, output is padded with = to a multiple of eight characters. The result is roughly 60% larger than the input — bigger than Base64's ~33% overhead, the price of the more forgiving alphabet.

Why the alphabet avoids certain characters

Base32 deliberately omits the digits 0, 1, 8 and 9 along with all lowercase letters. This avoids the classic confusions between 0/O, 1/I/l and 8/B, so a code read over the phone or copied off a screen is far less likely to be mistyped. That reliability is exactly why it is chosen for human-facing identifiers.

Where you'll meet it

The most common place is two-factor authentication: the secret keys behind TOTP/HOTP authenticator apps (Google Authenticator, Authy) are shared as Base32 strings. It also appears in Bech32-style cryptocurrency addresses, some DNS records, and any system where a value must survive being case-folded or read aloud without ambiguity.

Base32 versus Base64

Choose Base64 when size matters and the channel is fully binary-safe (data URIs, email attachments, API payloads). Choose Base32 when humans handle the value, case may not be preserved, or the data passes through systems that uppercase everything. This tool encodes UTF-8 text safely in either direction and runs entirely in your browser, so even authenticator secrets never leave your device.