Base32 Encoder / Decoder
Encode UTF-8 text to RFC 4648 Base32 or decode a Base32 value back to text.
- Runs locally in your browser
- No upload required
Try it
Supported formats
Privacy
Runs entirely in your browser. Your input is never uploaded, stored, or sent to a third party.
Encoded 5 character(s) of UTF-8 text to 8 Base32 character(s).
How it works
- Read the input as UTF-8 bytes.
- Packed the bytes into five-bit groups and mapped each to the A-Z2-7 alphabet.
- Padded the final block with '=' to a multiple of eight characters.
- Base32 is an encoding, not encryption; it provides no confidentiality.
- Base32 is larger than Base64 but survives systems that fold case or cannot carry punctuation.
Methodology
- Encode by packing UTF-8 bytes into five-bit groups and mapping each to the A-Z2-7 alphabet, padding the final block.
- Decode by reversing that mapping, ignoring optional padding and case, and rejecting a block length that only padding could produce.
- Treat the result as an encoding only: it provides no confidentiality.
Usage
- Choose encode or decode.
- Paste text to encode, or a Base32 value to decode.
- Read the result; use Copy result to reuse it.
Examples
These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.
Encode ASCII
{
"mode": "encode",
"value": "hello"
}Encode Unicode
{
"mode": "encode",
"value": "café 🌍"
}Decode a Base32 value
{
"mode": "decode",
"value": "NBSWY3DP"
}Limitations
Where Base32 is used
Base32 appears in one-time-password secrets, DNS records and anywhere a case-insensitive, human-transcribable token is needed. It is deliberately larger than Base64; choose it for robustness, not size.
Frequently asked questions
- Why is Base32 longer than Base64?
- Base32 uses five bits per character instead of six, so it needs more characters to represent the same bytes; the trade-off is a case-insensitive, punctuation-free alphabet.
- Does the decoder accept lower case?
- Yes. The encoder emits upper case, but decoding normalises the input to upper case first.
Sources
Send feedback
Tell us if this tool helped, report a problem, or suggest a tool. Only the message you type is sent — never the input you used in the tool.
Was this tool useful?
Prefer to write to us directly? See the contact page.