ToolKitSphereFree Online Base32 Encoder & Decoder
Encode text to Base32 format (RFC 4648) and decode Base32 strings.
43 characters · 9 words · 43 bytes (UTF-8)
Output will appear here
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This Base32 tool encodes text into RFC 4648-compliant Base32 format and decodes Base32 strings back to plain text, instantly in your browser. Base32 uses a restricted 32-character alphabet (A-Z and 2-7) that avoids visually ambiguous characters, which makes it popular for things that get typed or spoken by hand — TOTP two-factor authentication secrets, DNS-safe identifiers, and filesystem-friendly names are the most common uses you'll run into. Developers implementing 2FA/TOTP flows, sysadmins decoding authenticator app secrets, and anyone working with case-insensitive encoding needs will find this converter useful. Encoding and decoding both run entirely as JavaScript in your browser — no text, including sensitive TOTP seeds, is ever uploaded or logged on a server. There's no signup and no limits, and conversions happen instantly as you type. If you need standard Base64 instead, this platform has a dedicated Base64URL tool as well. Scroll down to encode or decode your Base32 string right now.
Features
- Full RFC 4648 Base32 encoding and decoding
- Instant client-side conversion, no server round trip
- Handles standard '=' padding correctly
- Case-insensitive decoding for convenience
- One-click copy to clipboard
- Compatible with TOTP/2FA authenticator secret formats
- Supports arbitrary-length UTF-8 input
- Works fully offline once loaded
Why use this base32 encode / decode?
- Instant encode/decode with no lag
- Fully private — text never leaves your browser
- RFC 4648 accurate, matching standard library output
- Simple two-way tool that's easy to use for beginners
- Free with unlimited use and no signup
Frequently asked questions
What is Base32 used for?
Base32 is commonly used for TOTP/2FA secret keys, DNS labels, filesystem names, and any context where a case-insensitive, human-typeable encoding is preferred over Base64.
Why use Base32 instead of Base64?
Base32's alphabet avoids visually similar characters (like 0/O and 1/I/l) and is case-insensitive, making it easier for people to read, type, and transcribe accurately by hand.
Is Base32 encryption?
No, Base32 is a reversible encoding scheme, not encryption — anyone can decode it back to the original data without a key.
How much larger is Base32 output than the original text?
Base32 encoding expands data by roughly 60%, since it uses 8 output characters to represent every 5 bytes of input.
Is Base32 the same format used for Google Authenticator secrets?
Yes, TOTP secrets used by Google Authenticator and similar apps are standard Base32-encoded strings following RFC 4648.
Does Base32 use padding characters?
Yes, standard Base32 pads output with '=' characters so the encoded length is a multiple of 8, though some implementations omit padding.
Is Base32 case-sensitive?
The standard alphabet is uppercase, but most decoders, including this one, accept lowercase input for convenience.