Base62 Encode / Decode
About Base62 Encoder
Base62 encodes data using only the 62 alphanumeric characters 0–9, A–Z and a–z. Because it has no +, /, = or other symbols, Base62 strings are safe in URLs, file names and identifiers without any escaping — which is why it is popular for URL shorteners and short IDs.
This tool encodes text (as UTF-8 bytes) to Base62 using the common 0-9A-Za-z alphabet and decodes it back. Input can also be processed line by line.
How to use
- Enter text to encode, or a Base62 string to decode.
- Click
EncodeorDecode. - Enable
Line-by-lineto process each line separately, andAuto updateto re-run as you type.
FAQ
Base62 vs Base64 — what is the difference?
Base64 uses 64 symbols including + and / and needs padding, so it must be escaped in URLs. Base62 avoids those characters at the cost of slightly longer output and more expensive big-number arithmetic.
Why does my Base62 output differ from another library?
There is no single Base62 standard. Libraries differ in alphabet order (0-9A-Za-z vs 0-9a-zA-Z) and in how they handle leading zero bytes. This tool uses 0-9A-Za-z.
Is Base62 reversible?
Yes. Encoding treats the bytes as one large number and converts it to base 62; decoding converts it back, and leading zero bytes are preserved as leading 0 characters.