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Guide

UUID Validator & Formatter Online — Check Format, Version & Reformat GUID

Free UUID validator and formatter online: paste a UUID or GUID to check version, then reformat with hyphens, uppercase, or braces. Instant UUID checker—runs in your browser.

By Spoold Editorial TeamReviewed for tool accuracy
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#uuid validator#uuid formatter#uuid validator online#validate uuid#guid validator#RFC 4122#Developer Tools

Validate a UUID—then format it.

Searching for a UUID validator or UUID formatter? Spoold's UUID Validator & Formatter checks format, version, and variant, then reformats with hyphens / uppercase / braces. Need new IDs? Use the UUID Generator.

Open the UUID validator →

What the validator checks

Canonical UUIDs look like 8-4-4-4-12 hex digits. A good UUID checker also reads the version nibble (v1, v4, v7…) and variant bits so you know whether a string is a random v4, a time-ordered v7, or just “looks UUID-shaped.” Spoold also accepts compact hex and braced GUIDs.

Example formats

550e8400-e29b-41d4-a716-446655440000
{6BA7B810-9DAD-11D1-80B4-00C04FD430C8}
550e8400e29b41d4a716446655440000

Paste any of these into the validator, then toggle hyphens / uppercase / braces and copy the formatted result.

When to validate

API payloads

Confirm a client sent a real UUID before you hit the database unique index.

Logs & support

Spot truncated or double-braced GUIDs copied from Windows tools.

Format for target system

Some APIs want uppercase, no hyphens, or {GUID} braces—reformat in one click.

Generate vs validate

Bulk create with the generator; single-string checks stay on the validator.

How to validate & format on Spoold

  1. Open /tools/uuid-validator.
  2. Paste one UUID or GUID (hyphenated, compact, or braced).
  3. Read version / validity.
  4. Toggle hyphens, uppercase, braces → Copy formatted.

Tip: GUID = UUID

Microsoft's GUID is the same 128-bit layout. Uppercase and braces are presentation—validation still applies.

Related guides

Related search terms

uuid validatoruuid validator onlineuuid formatterformat uuidguid validatorvalidate uuiduuid uppercaseuuid without hyphensrfc 4122 uuid

Frequently asked questions

Is the UUID validator free?
Yes—client-side, no sign-up.
Can I format without regenerating?
Yes. Paste an existing UUID and use the format toggles (hyphens / case / braces), then copy.
Do you accept braces or no hyphens?
Yes—compact 32-hex and {GUID} forms normalize before version detection.
Can I validate many UUIDs at once?
The online checker is optimized for one string. Split bulk lists first, or generate batches on the UUID Generator page.
v4 vs v7?
v4 is random; v7 is time-ordered (better DB index locality). The validator reports the version nibble when the string is valid.

Validate a UUID

Paste an ID into the UUID validator online.

UUID ValidatorUUID GeneratorULID Generator

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UUID Validator & Formatter Online — Check Format, Version & Reformat GUID | Blog | Spoold