THE PRACTICAL GUIDE · NORMANDIN SYSTEMS
Get more from ULID generator
ULID Generator creates Universally Unique Lexicographically Sortable Identifiers in raw text or JSON form. A ULID combines a millisecond timestamp component with a random component and represents the result as a 26-character string. This makes it useful for sample record identifiers and systems that benefit from broadly time-ordered string keys. Generate a small batch first and check the output format expected by the receiving system. The timestamp is part of the identifier, so ULIDs should not be treated as secret tokens. Sorting can reflect timestamp order, but it does not prove a complete ordering of distributed events or eliminate the need for database uniqueness constraints.
Guide updated October 13, 2026
How to use this tool
- Choose the number of identifiers to generate within the quantity range shown by the tool.
- Select raw output for one identifier per line or JSON when the receiving workflow expects an array of strings.
- Generate or refresh the batch, then inspect the identifier count and representation before copying.
- Store the values as strings. Keep a uniqueness constraint in any system where duplicate identifiers would be harmful.
SEE IT IN PRACTICE
A worked example
Quantity 1; raw format
An identifier shaped like 01ARZ3NDEKTSV4RRFFQ69G5FAV
This is a format example. Each generated value depends on the generation time and randomness, so a fresh run should not be expected to reproduce this exact string.
Storage and ordering decisions
Use a string column or another representation that preserves all identifier characters. A database collation can affect ordering or case comparisons, so test the actual index and sorting behavior used by the application. The timestamp component makes time-based grouping convenient, but concurrent producers and clock differences mean a sorted list is not a complete history of causality.
Raw output and JSON output
Raw mode gives one identifier per line, suitable for a line-oriented fixture. JSON mode supplies a quoted array of strings. Preserve that distinction when pasting into another tool: removing quotes can turn a valid JSON fixture into invalid syntax. A fresh batch is intentionally different from an earlier one, so save fixed values when a reproducible test requires stable identifiers rather than regenerating them during every assertion.
When this tool is useful
- Create synthetic identifiers for test records and example datasets.
- Explore how timestamp-prefixed string identifiers sort in a database or file.
- Prepare an array of identifiers for a fixture without typing placeholder keys manually.
Tips for a better result
- A ULID is not a password or an authorization token. Its timestamp component exposes approximate generation time.
- Do not assume values created within the same millisecond are monotonic; that requires a particular generation strategy.
- Keep identifiers as complete strings and use a consistent case convention if your storage or comparison system is case-sensitive.
Frequently asked questions
Why are ULIDs sortable?
Their timestamp component appears before their random component in a fixed-width encoding, so lexicographic ordering can follow timestamp ordering. This is useful for grouping records by generation time but does not prove causal order.
Are collisions impossible?
No randomly generated identifier scheme should be treated as an absolute guarantee. The design makes accidental collisions unlikely under appropriate generation, but applications should still enforce uniqueness where required.
How is a ULID different from a secret token?
A ULID is designed to identify records and includes time information. A secret token has a security role and must be generated, stored, and validated according to that role; an identifier alone should not grant access.
What happens to the information I enter?
The utility processes your input in this browser. Some tools retain field values in browser storage or the URL; avoid entering secrets in shareable fields. Page and asset requests still go to the hosting provider. Read the privacy and offline-use notes for details.