Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
UUID Validator
Validate, analyze, and generate UUIDs — detect version, variant, and extract timestamps
- Home
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- UUID Validator
Results
Enter UUIDs and click Validate
What Is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier standardized by RFC 9562 (formerly RFC 4122). UUIDs are designed to be unique across space and time without requiring a central registration authority. They are commonly used as database primary keys, API resource identifiers, session tokens, and distributed system identifiers. UUIDs have different versions: v1 (time-based, using timestamp and MAC address), v4 (random), v7 (time-ordered random), and others. This tool validates UUID strings, detects their version (v1 through v8) and variant (RFC 9562, Microsoft, Reserved), and for time-based UUIDs (v1, v6, v7), extracts the embedded timestamp. It also supports bulk validation for analyzing multiple UUIDs at once. UUID validation is essential for data integrity, API request checking, and database import verification.
How to Use This Tool
- Enter UUIDs — Type or paste one or more UUIDs into the input area (one per line for multiple).
- Click Validate — The tool checks each UUID's format, detects its version and variant, and displays the results.
- Review analysis — Each UUID shows its validity status, version number, variant type, and for time-based UUIDs, the embedded timestamp.
- Generate UUIDs — Click Generate v4 for a random UUID or Generate v7 for a time-ordered UUID.
- Use examples — Click the example buttons (v4, v1, v7, Mixed) to see different UUID types and their analysis.
Frequently Asked Questions
Is my data sent to a server?
No. All processing is performed locally in your browser. Your UUIDs never leave your device.
What UUID versions are supported?
The validator supports versions v1 through v8 as defined by RFC 9562. It can identify the version from the UUID's variant and version bits.
Can UUIDs be reverse-engineered?
v1 UUIDs contain a timestamp and MAC address, which could reveal when and where the UUID was generated. v4 (random) and v7 (time-ordered random) UUIDs do not expose hardware information.
What is the difference between UUID v4 and v7?
v4 UUIDs are fully random, while v7 UUIDs are time-ordered with random sub-millisecond precision, making them more efficient for database indexing.
Is this tool free to use?
Yes. This tool is completely free with no usage limits or registration required.
Last updated: 17 Aug 2026
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