Generate UUID v7 for Databases (Why Sortable IDs Help)
Random UUID v4 IDs are ubiquitous, but they scatter inserts across B-tree indexes. UUID v7 embeds a timestamp so new IDs roughly sort by creation time — often friendlier for databases and logs.
UUID v4 vs UUID v7
v4 is random. Great for uniqueness, weaker for locality. v7 is time-ordered with random bits for uniqueness, improving insert locality in many relational stores.
- v4: maximum randomness, widely supported
- v7: sortable by time, better index locality for append-heavy tables
- Both remain 128-bit UUIDs in standard string form
When to choose v7
Choose v7 for primary keys on high-write tables, event streams, and systems where chronological ordering helps debugging — after confirming library and database support in your stack.
Generate UUID v7 quickly
Use the UUID Generator to create bulk UUIDs including v7 for local testing, seed data, and documentation examples.
- Open the UUID Generator.
- Select UUID version v7.
- Generate one or many IDs and copy them into migrations or fixtures.
Key takeaways
- UUID v7 adds time-ordering while staying a standard UUID.
- It can improve insert locality versus random v4 keys.
- Generate test IDs instantly with the UUID Generator.
Try the related tool
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UUID GeneratorFrequently Asked Questions
Is UUID v7 standardized?
UUID v7 is part of the modern UUID specification (RFC 9562). Support continues to grow across languages and databases.
Should I replace all v4 IDs with v7?
Not blindly. New tables and greenfield services are the best candidates. Migrating existing keys needs a careful plan.
Can I generate UUIDs without an account?
Yes. The EazyTools4u UUID Generator is free and runs in your browser.