How to use the ULID & Nano ID Generator
- Choose ULID for IDs that sort by time (great as database keys), or Nano ID for short, random, URL-friendly IDs.
- Set how many to generate — up to 1,000. For ULIDs keep monotonic on so IDs made in the same millisecond still sort in order.
- For Nano IDs pick the length and alphabet (or type your own) and an optional prefix like
usr_; the collision risk panel shows if it is long enough. - Copy or download the list. Paste a ULID into Decode to see when it was created.
ULID vs Nano ID vs UUID
| ULID | Nano ID (default) | UUID v4 | |
|---|---|---|---|
| Length | 26 characters | 21 characters | 36 characters |
| Randomness | 80 bits + 48-bit timestamp | 126 bits | 122 bits |
| Sorts by time | Yes | No | No (v7 does) |
| URL-safe | Yes (Crockford Base32) | Yes | Yes, but long |
A ULID starts with a 10-character timestamp (milliseconds since 1970) followed by 16 random characters, in Crockford’s Base32 alphabet — no I, L, O or U, so it is hard to misread. Because the time comes first, ULIDs sort in creation order, which keeps database indexes compact. A Nano ID is pure randomness: with the default 21 URL-safe characters you would need to create a billion IDs every second for about 40 years before there is a 1% chance of a single duplicate.
Both are generated with crypto.getRandomValues, without the bias of Math.random() or modulo tricks. Need standard UUIDs? Use the UUID Generator.
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Tools that pair well with the ULID & Nano ID Generator
- Password Generator — Create strong, truly random passwords or easy-to-type passphrases — with advanced rules: include or exclude words, require characters, choose allowed symbols, avoid repeats and sequences.
- Hash Generator — Compute MD5 and SHA hashes of any text or file instantly, create HMAC signatures, and paste an expected checksum to verify a download.
- Random Number Generator — Generate random numbers (with or without duplicates), pick winners from a list, shuffle names, split groups into teams, flip coins and roll dice — using your browser’s cryptographically secure randomness.
- Unix Timestamp Converter — See the current Unix time live, convert any epoch timestamp (seconds, milliseconds, micro- or nanoseconds) to a date in any time zone, and turn dates back into timestamps.