How do I generate a UUIDv7 in JavaScript?

Use the uuid npm package: import { v7 as uuidv7 } from 'uuid'; const id = uuidv7();

Can I extract the timestamp from a UUIDv7?

Yes! The first 48 bits contain a Unix timestamp in milliseconds. Use our parser tool to extract it instantly.

Is UUIDv7 better than UUIDv4?

For database primary keys, yes—UUIDv7 offers better index performance and timestamp extraction. UUIDv4 remains suitable when ordering doesn't matter.

Can UUIDv7 be used as a database primary key?

Absolutely! UUIDv7 is ideal for primary keys. Its time-ordered nature means new records are inserted at the end of B-tree indexes, avoiding page splits and improving write performance.

How long until UUIDv7 timestamps overflow?

The 48-bit timestamp will overflow around the year 10889 AD (over 8,800 years from now), calculated from 2^48 milliseconds from Unix epoch (1970).

What is monotonic UUIDv7?

Monotonic UUIDv7 ensures strict ordering even when multiple UUIDs are generated within the same millisecond. Instead of random bits, a counter increments in the rand_a field.

What RFC defines UUIDv7?

RFC 9562, published May 2024, superseding RFC 4122.

RFC 9562

UUIDv7 Generator
& Parser

Generate time-ordered unique identifiers, parse existing UUIDs, and extract embedded timestamps.

Generator

Monotonic (sequential)

Batch

Documentation

What is UUIDv7?

UUIDv7 is a time-ordered UUID format defined in RFC 9562. It combines a Unix timestamp in milliseconds with cryptographically random data to create sortable, unique identifiers ideal for distributed systems and databases.

Structure (128 bits)

Field	Bits	Description
unix_ts_ms	48	Unix timestamp (ms)
ver	4	Version (7)
rand_a	12	Random data
var	2	Variant (10)
rand_b	62	Random data

Visual Format

xxxxxxxx-xxxx-7xxx-yxxx-xxxxxxxxxxxx

timestamp version rand_a variant rand_b

Benefits

Time-Ordered

UUIDs sort chronologically for efficient indexing.

Distributed

Generate unique IDs without coordination.

DB Efficient

Sequential inserts improve B-tree performance.

Collision Safe

74 random bits prevent collisions.

Comparison

Ver	Time	Sort	Use
V1	✓	✗	Legacy
V4	✗	✗	Random
V6	✓	✓	Migration
V7	✓	✓	Modern ★

FAQ

Generate in JavaScript

import { v7 as uuidv7 } from 'uuid';
const id = uuidv7();

Extract Timestamp?

Yes. First 48 bits = Unix ms timestamp. Use the parser tab.

V7 vs V4?

V7 is better for DB primary keys (sorted inserts). V4 is fine when ordering doesn't matter.

Timestamp Overflow?

Year 10889 AD. The 48-bit timestamp lasts ~8,800 years from 1970.

What is Monotonic?

Ensures strict ordering within same ms using counter instead of random bits.

RFC Spec?

RFC 9562 (May 2024), supersedes RFC 4122.

UUIDv7 Generator & Parser