ULID Generator & decoder

Generate cryptographically random ULIDs in your browser, batch up to 500, and decode timestamps from existing ULIDs. No server calls.

100% local — your data never leaves this device

ULIDs are 26-character Crockford base32 strings: 48 bits of UTC millisecond time (first 10 characters) plus 80 bits of randomness (last 16). They sort chronologically as plain text.

Single ULID

Bulk generation

You can generate between 1 and 500 ULIDs per batch.

Decode ULID

Paste a 26-character ULID to read its embedded timestamp and random payload.

Decoded details will appear here.

How to use ULID Generator

  1. 1Choose letter case and click Generate ULID for one new value, or generate a batch (1–500) with one per line.
  2. 2Paste any ULID into the decoder and click Decode to see UTC, local time, unix milliseconds, and the random part as hex.
  3. 3Use Copy on the output area to grab generated ULIDs for logs, databases, or APIs.

Privacy

Randomness uses Web Crypto (getRandomValues). Parsing and decoding run entirely in your browser; nothing is uploaded or logged.

🔒 Processed locally in your browser. ULIDs are never sent to a server.