Online ULID generator
Your generated ULID
Bulk ID generator
You can generate up to 1000 IDs at a time using the Bulk ID Generator. Select the ID version you require by selecting it from the drop-down list.
ULID in a nutshell
Universally Unique Lexicographically Sortable Identifier
The Universally Unique Lexicographically Sortable Identifier (ULID) is a 128-bit identifier designed for uniqueness and lexicographic sorting in distributed systems. It consists of two main components:
The ULID incorporates a 48-bit timestamp, providing a time-based element to the identifier. This timestamp is Unix time in milliseconds, and it ensures that ULIDs generated at different locations and times are inherently ordered.
The remaining 80 bits are dedicated to randomness. Unlike some traditional UUIDs, which rely solely on randomness, ULIDs combine this random component with a timestamp, offering a balance between uniqueness and sortability.
Key characteristics of ULIDs include:
ULIDs are highly unlikely to collide, even in distributed environments, due to the combination of timestamp and randomness.
The lexicographic sorting of ULIDs preserves the chronological order of their creation, making them suitable for use cases where ordered identifiers are valuable, such as in distributed databases and logs.
ULIDs are typically represented as a 26-character string using a modified Base32 encoding. This representation is both compact and human-readable.
ULID is a great alternative to UUID v1 for distributed systems, as it provides a unique identifier that is both lexicographically sortable and time sortable.