Why this tool is useful
Use ULIDs when lexicographic ordering by creation time is useful, or inspect an existing value before treating its embedded timestamp as trustworthy metadata.
Developer & Data · runs locally
ULID Generator and Inspector
Generate cryptographically random canonical ULIDs or inspect case-insensitive input as an uppercase 48-bit timestamp and 80-bit randomness value entirely in the browser.
Ready. Your working data stays in this browser.
How it works
The generator combines the current 48-bit Unix millisecond value with 80 Web Crypto random bits and encodes them with canonical Crockford Base32; inspection rejects overflow and noncanonical characters.
Practical example
Inspecting 01ARZ3NDEKTSV4RRFFQ69G5FAV reports its UTC timestamp and separates the ten-character time prefix from the sixteen-character random suffix.
Validation
The calculation is deterministic and explains validation errors instead of silently changing invalid input.
Privacy boundary
Input and output remain in this tab. Copy and download happen through browser APIs without a server upload.
Result passport
Every run reports its tool mode, timestamp and input/output size so transformed data can be audited.