Base32 Encoder / Decoder

What is Base32?

Base32 is a binary-to-text encoding scheme defined in RFC 4648. It encodes binary data into a sequence of 32 ASCII characters, using letters A–Z and digits 2–7. Unlike Base64, Base32 is case-insensitive and avoids characters that can be confused in certain contexts. It's commonly used in authenticator apps, DNS DNSSEC, and distributed systems. Base32 is also more resilient to OCR errors when printed.

How to Use This Tool

To encode text to Base32: Paste or type your text into the textarea, select your variant, then click "Encode". The output appears in the green box below.

To decode Base32 to text: Paste Base32-encoded text, ensure you're using the correct variant, then click "Decode". If decoding fails, you'll see an error message.

You can toggle padding (the = characters at the end) on and off. The byte breakdown shows how the input is split into 5-bit chunks for Base32 encoding.

Base32 Variants

Standard Base32 (RFC 4648): Uses A–Z (26 letters) + 2–7 (8 digits). Most common variant.

Base32 Hex: Uses 0–9 + A–V for better alphabetical ordering. Useful when sorted order matters.

Crockford Base32: A variant designed by Douglas Crockford that avoids confusing characters (no I, L, O, U) to reduce transcription errors.

What's the difference between Base32 and Base64?

Base32 uses 32 characters (letters and digits 2–7) while Base64 uses 64 characters (letters, digits, +, /). Base32 produces longer output but is case-insensitive and avoids special characters that might be problematic in certain contexts. Base64 is more space-efficient.

Why would I use Base32 instead of Base64?

Base32 is ideal when case-insensitivity or character restrictions matter. It's widely used in authenticator tokens (TOTP/HOTP in RFC 6238), DNS records, and any system where you want to avoid special characters like + and /. It's also better for handwritten or OCR-scanned documents.

Does this tool work offline?

Yes! This tool runs entirely in your browser. No data is sent to any server. Once the page loads, you can encode and decode completely offline. All processing happens on your device.

Can I decode any Base32 string?

Base32 can decode any valid Base32 string (containing only valid characters for the chosen variant). However, decoded output is interpreted as UTF-8 text—if the original input wasn't valid UTF-8, you'll see an error. You can always encode/decode bytes using the Base16 (hex) format instead.

What does "padding" mean?

Base32 pads the output with '=' characters to align the encoded length to a multiple of 8. Padding is required by RFC 4648 but optional in some contexts. This tool lets you toggle it for flexibility. Most decoders handle padded or unpadded input correctly.

Is this tool secure?

Base32 is not an encryption algorithm—it's an encoding scheme. If you need to protect sensitive data, encrypt it first, then encode. This tool does not encrypt or hash anything. Use it for format conversion only.