ページを読み込んでいます
Generate UUID v4, UUID v7, and ULID. Supports batch generation and various format options.
Choose the format you want to generate: UUID v4 (random), UUID v7 (timestamp-based), or ULID.
Set uppercase/lowercase, with or without hyphens, and the number of IDs to generate (1-100).
Click 'Generate' and then 'Copy' to copy the generated IDs to clipboard.
Integer from 1 to 100
No history
UUID/ULID Generator is an online tool that generates unique identifiers (unique IDs). It's useful for database primary keys, API identifiers, and any situation requiring non-duplicate identifiers. It supports three formats: UUID v4 (fully random), UUID v7 (timestamp-based), and ULID (sortable).
UUID v4 has 122 random bits and is a completely random identifier. UUID v7 includes a timestamp at the beginning, making it sortable by generation time. ULID is also time-sortable but uses 26-character Base32 format, making it shorter than UUID and suitable for URLs and filenames.
Theoretically yes, but for UUID v4, the collision probability is extremely low (about 2^122 possibilities). Even generating 1 billion IDs per second, it would take approximately 85 years for a collision to occur.
UUID v7 or ULID is recommended. Since they can be sorted by timestamp, B-tree index efficiency is good and insert performance improves. UUID v4 is random, so indexes tend to fragment.
Use it when hyphens are inconvenient, such as in URL parameters or filenames. The result is a continuous 32-character string, but uniqueness remains the same.
No, all processing happens entirely in your browser. It uses a cryptographically secure random number generator (crypto.getRandomValues), and generated IDs are never sent to any server.