Base 62 Encoder

Encode text to Base62, or decode Base62 back to text — copy and paste the result.

This free online tool lets you base 62 encode any text — alphanumeric output only (0-9, A-Z, a-z), no padding, no symbols, safe to drop straight into a URL. Decode a Base62 string back to text with one click. No signup required, runs entirely in your browser.

Examples:

Mode

Quick reference

1Z
→ "a"
1wJfrzvdbtXUOlUjUf
→ "Hello, World!"
0-9, A-Z, a-z
the full alphabet (62 symbols)
no padding
unlike Base32/Base64

What is Base62 encoding?

A base 62 encoder converts text or binary data into a compact alphanumeric string using 62 symbols: the digits 0-9, uppercase letters A-Z, and lowercase letters a-z. Unlike Base32 and Base64, Base62 has no official RFC — it's a de facto convention built around big-integer conversion rather than fixed-width byte grouping. The input's bytes are treated as one large number and rewritten in base 62, the same way you'd convert a number from decimal to hexadecimal, just with a bigger alphabet.

Because the alphabet contains only letters and digits — no +, /, =, or any other symbol — Base62 output is naturally safe to use in a URL path, a filename, or a database column with zero escaping. That's why it's the go-to encoding behind most URL shorteners and short-ID systems.

How to encode text to Base62 online

Type or paste your text into the input above with the mode set to Text → Base62. The encoder reads the UTF-8 bytes of your input, treats them as one big integer, and converts that integer to base 62 using the browser's native BigInt. Leading zero bytes are handled correctly — each maps to a leading 0 character in the output, so no information is lost.

How to decode Base62 back to text

Switch the mode to Base62 → Text and paste your Base62 string. The decoder reverses the process: it converts the base-62 digits back into a big integer, then splits that integer back into bytes and decodes them as UTF-8 text.

Base62 vs Base32 vs Base64

  • Base62 — alphanumeric only, no padding, most compact of the three. Best for URL-safe short IDs and shortened links.
  • Base64 — 64-character alphabet including symbols, fixed-block encoding with = padding. Best for compact machine-to-machine encoding (data URLs, JWTs, MIME attachments).
  • Base32 — 32-character alphabet, case-insensitive, avoids ambiguous characters. Best for values a human has to read or type by hand (TOTP/2FA secrets).

Working with other encoded formats? See the Base64 Converter or the Base 32 Decoder.

Common Base62 use cases

  • URL shorteners — turning a large numeric database ID into a short, shareable code (the technique behind services like bit.ly).
  • Short unique IDs — compact identifiers for orders, invites, or short links, generated from a counter or random number.
  • ID obfuscation — making sequential database primary keys look non-sequential in a public-facing URL, without needing a separate lookup table.

Frequently asked questions

Base62 represents binary data as a big number written in base 62, using the alphabet 0-9, A-Z, then a-z (62 symbols total). Unlike Base32/Base64, there's no official RFC — Base62 is a de facto convention, most commonly used to shorten numeric IDs into compact, URL-safe strings for things like URL shorteners and database primary keys.
Type or paste your text into the input above with the mode set to Text → Base62. The encoder treats the UTF-8 bytes of your input as one large number and converts it to base 62, so the output uses only letters and digits — no symbols, no padding.
Base32 and Base64 pad their output to a fixed block size because they process data in fixed-width bit groups. Base62 works differently — it converts the entire input into one big integer and writes that integer in base 62, so there's no block size to pad to. The output length simply reflects the size of the number.
Base64 uses a 64-character alphabet that includes '+' and '/' (or '-' and '_' for the URL-safe variant), and processes data in fixed 3-byte/4-character blocks with '=' padding. Base62 uses only alphanumeric characters (0-9, A-Z, a-z) — no symbols at all — which makes it naturally safe to drop into a URL path, filename, or database column without any escaping, at the cost of being a big-integer conversion rather than a simple byte-group mapping.
The most common use is URL shorteners and short ID generators — converting a large numeric database ID into a compact alphanumeric string so links look clean and are easy to share. It's also used to obfuscate sequential IDs without needing a lookup table.
No. Everything is encoded and decoded locally with JavaScript in your browser. Nothing is uploaded or stored on a server.
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