ULID Generator
Generate ULIDs instantly. ULID combines millisecond precision timestamp with random data for unique, sortable 128-bit identifiers.
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What is ULID Generator?
ULID Generator creates Universally Unique Lexicographically Sortable Identifiers. Unlike UUIDs, ULIDs are sortable by time, use a base32 encoding which omits ambiguous characters (I, L, O, U), and pack a millisecond-precision timestamp with random data into a 128-bit structure.
Key Benefits
- Lexicographically sortable
- 128-bit compatibility with UUID
- URL-safe without special characters
- Bulk generation (up to 100)
Common Use Cases
- •Database primary keys
- •Event sourcing systems
- •Log line identifiers
- •Distributed systems
- •Time-series data
How to Generate ULID
- Set the amount of ULIDs: Enter a number between 1 to 100 to configure how many ULIDs you want to generate in a single batch.
- Click generate: Press the "Generate" button, generating all the requested ULIDs instantaneously.
- Copy identifiers: Click on individual ULIDs to copy them, or click "Copy All" to get the whole list copied strictly to your clipboard.
Key Features
- Immediate lexicographically sortable identifier generation
- URL-safe base32 encoding output
- Configurable bulk generation up to 100 ULIDs at once
- Copy-all and individual copy functionalities
- Zero dependencies, works completely offline
- Compatible with 128-bit UUID database columns
Frequently Asked Questions
What is a ULID?
ULID stands for Universally Unique Lexicographically Sortable Identifier. It is a 128-bit identifier that combines a 48-bit timestamp with 80-bits of cryptographically secure randomness. It solves the performance issues UUIDv4 causes in database indexes by allowing sorting by time.
Why choose ULID over UUID?
ULIDs are lexicographically sortable, which means they are great for database primary keys and indexing since they are ordered by time of generation. They are also URL-safe, shorter (26 characters vs 36 for UUID), and encode using Crockfords Base32 (no I, L, O, or U to avoid user confusion).
Are ULIDs cryptographically secure?
Yes, the 80 bits of random data in a ULID are generated using a Cryptographically Secure Pseudo-Random Number Generator (CSPRNG), providing robust uniqueness to prevent collisions even when generating millions of ULIDs per millisecond.
Is ULID compatible with UUID?
Yes, both ULID and UUID are 128-bit identifiers. You can store a ULID in a standard UUID backend column (like a UUID type in PostgreSQL) by converting its format, although the canonical text representation is different.