Time-Ordered UUID v7 Generator | Nadhebe

GENERATION PARAMETERS

Quantity to Generate (1 to 50)

GENERATED TIME-ORDERED UUID v7 LIST

UUID v7 Output

UUID v7 Optimization Guide — High-Performance Database Primary Keys

RFC 9562 standardizes UUID v7 as the modern successor to UUID v4. By embedding a 48-bit millisecond timestamp in the leading bits, UUID v7 provides sequential B-Tree index insertions while guaranteeing global uniqueness across distributed systems.

Comparison: UUID v4 vs UUID v7

UUID v4: Cryptographically random. Causes 40%+ B-Tree index page splitting and high disk I/O.
UUID v7: Time-ordered. Appends sequentially to database indexes, maintaining peak write performance.

Related Developer Tools

Generate standard UUID v4 with the UUID Generator, validate schemas with the JSON Schema Validator, or format SQL queries with the SQL Formatter.

Frequently Asked Questions

Common questions about this tool.

What is a UUID v7 identifier? ▼

UUID v7 (RFC 9562) is a 128-bit time-ordered unique identifier that embeds a 48-bit Unix timestamp in its most significant bits, followed by cryptographically random bits.

Why is UUID v7 better than UUID v4 for database primary keys? ▼

Random UUID v4 causes severe database index fragmentation and random disk I/O in B-Tree indexes. Time-ordered UUID v7 enables sequential append-only index insertion.

What is the structure of a UUID v7 string? ▼

A 36-character string in `8-4-4-4-12` hex format. The first 12 hex characters represent the Unix millisecond timestamp.

Is UUID v7 supported in modern databases? ▼

Yes! PostgreSQL, MySQL 8+, SQLite, and MongoDB support UUID v7 as a native or 128-bit binary column type.

Can I extract the creation timestamp from a UUID v7 string? ▼

Yes! The first 48 bits contain the millisecond timestamp, allowing you to extract exact creation times without storing a separate `created_at` column.