Nil UUID Generator

Generate and copy the standardized all-zero nil UUID for placeholders, defaults, and sentinel values.

Nil UUID
Copy the standardized all-zero UUID in the representation your system expects.
Always returns the same value
Canonical UUID
00000000-0000-0000-0000-000000000000
32-digit hex
00000000000000000000000000000000
UUID URN
urn:uuid:00000000-0000-0000-0000-000000000000
Reference
The nil UUID is a fixed sentinel value, not a random identifier.
Bits
128 zero bits
Version
None
Variant
None
Regeneration
Always returns the same value

What Is a Nil UUID?

A nil UUID is the standardized UUID whose 128 bits are all zero. Its canonical text form is 00000000-0000-0000-0000-000000000000, and it is often used to mean “no UUID has been assigned yet.”

When to Use It

Use a nil UUID when an API, database column, fixture, or configuration file requires a UUID-shaped value but the real identifier is intentionally absent. It is useful as a placeholder in tests, import templates, migration scripts, and protocols that define an explicit empty UUID value.

What to Watch For

Do not treat the nil UUID as a generated unique identifier. It is the same value every time, so storing it where a real object ID is expected can hide missing data, break uniqueness assumptions, or make records look connected when they are not.