UUID Generator
Generate UUIDs v1, v4, and v7 in bulk. Copy individually or all at once. Everything runs in your browser — no data sent anywhere.
🔑 UUID v4
Randomly generated. The most common version — use this when you need a unique ID and don't need any embedded information.
🕐 UUID v1
Time-based. Encodes the current timestamp and MAC address. Useful when you want sortable, time-ordered IDs.
⚡ UUID v7
The modern choice. Time-ordered like v1 but uses random data instead of MAC address. Ideal for database primary keys.
📋 Bulk generate
Generate up to 100 UUIDs at once. Copy individually or grab them all in one click.
🔒 100% private
All UUIDs are generated in your browser using the Web Crypto API. Nothing is sent to any server.
💡 When to use UUIDs
Database primary keys, API resource identifiers, distributed system IDs, session tokens, and anywhere you need globally unique values.
How to use the UUID Generator
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier standardized as a 32-character hex string in the format xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. UUIDs are designed to be unique across all machines and all time without requiring a central authority to coordinate. The probability of generating two identical UUID v4s is astronomically low — roughly 1 in 5.3 × 1036.
UUID v1 vs v4 vs v7 — which to use?
UUID v1 is time-based and includes the MAC address of the generating machine — it's sortable by time but leaks network information. UUID v4 is completely random — the most widely used version, ideal for database primary keys, session tokens, and any identifier where security matters. UUID v7 is a newer time-ordered random UUID that combines the best of both: it's random enough to be secure but sortable by creation time, making it ideal for database indexes where insert performance matters.
UUIDs as database primary keys
UUIDs make excellent primary keys in distributed systems because they can be generated client-side without a database round-trip, preventing ID collisions across multiple servers or shards. The tradeoff is size — a UUID takes 36 bytes as a string vs 8 bytes for a bigint. For most applications this is acceptable. Use UUID v7 if you need both uniqueness and index-friendly ordering.
Common use cases
UUIDs are used as database primary keys, session identifiers, API keys, file names for uploaded assets, request trace IDs for distributed logging, idempotency keys for payment APIs, and correlation IDs in microservices. Any time you need a unique identifier that doesn't expose sequential information about your data, a UUID is the right choice.