UUID guides
Short articles about UUIDs, GUIDs and other IDs, in plain English. Each one answers a single question, with examples you can copy.
FeaturedCode · 2 min read
How to get the timestamp from a UUID v7
Every UUID v7 carries the moment it was created. Learn where it hides, then read it with one line of JavaScript, Python or SQL.
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Comparisons · 6 min read
UUID vs ULID vs Nano ID: which should you pick?
Length, sorting and safety compared, with a simple way to choose.
Databases · 6 min read
How to store UUIDs in PostgreSQL and MySQL
Which column type to use, and how to keep your indexes fast.
Code · 5 min read
How to generate a UUID in Python
uuid4, uuid5 and the newer uuid7, with copy-ready examples.
Basics · 6 min read
How likely is a UUID collision?
The real odds of two UUIDs matching, explained without the maths.
Basics · 5 min read
What is a GUID, and is it a UUID?
How Microsoft's GUID relates to UUID, and the byte-order catch.
Comparisons · 5 min read
UUID v4 vs v7: which should you use?
Random or time-sorted? A clear answer for databases and APIs.
Comparisons · 5 min read
UUID v1 vs v6 vs v7
Three time-based versions, and which one to pick today.
Basics · 5 min read
Is it safe to show UUIDs in URLs?
What a UUID can reveal, and when to use something else.
Code · 6 min read
How to check if a string is a valid UUID
A regex that works, plus the edge cases it misses.
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