UUID Generator Online

This UUID Generator (also known as GUID) creates ready-to-use identifiers for apps, databases, APIs, test data, logs, migrations, and documentation. You can generate random UUID v4 values or timestamp-based UUID v7 values, then copy them as plain lines, comma lists, JSON arrays, SQL values, quoted strings, URNs, or no-hyphen IDs.

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What this UUID generator does

The tool generates one UUID or a bulk list of up to 1,000 UUIDs. It also lets you choose the version, letter case, output format, and separator, so the result is ready to paste into code, spreadsheets, database scripts, API payloads, or config files.

• UUID v4: best for random identifiers, public IDs, tokens, database records, test data, and general development.
• UUID v7: best when you want IDs that include creation-time order, useful for logs, events, database rows, and distributed systems.
• Bulk generation: useful for mock records, seed data, import files, QA testing, and sample datasets.
• Format options: standard UUIDs, no hyphens, braces, URNs, quoted strings, JSON arrays, and SQL values.
• UUID checker: validates pasted UUIDs, detects the version, checks the variant, and shows the timestamp for UUID v7.

When to use UUID v4

Use UUID v4 when you need a random ID that does not reveal when it was created. It is the normal choice for public record IDs, API objects, database primary keys, temporary test data, tracking records, internal tools, and generated filenames.

UUID v4 is usually the safest default when you only need uniqueness and do not care about sorting by creation time.

When to use UUID v7

Use UUID v7 when you want IDs that sort better by creation time. This can help with database indexes, event logs, analytics records, queues, audit trails, and systems where new records are constantly inserted.

UUID v7 can reveal the approximate creation time, so use UUID v4 instead if timestamp privacy matters.

Common output formats

How to use the UUID checker

Paste any UUID into the checker to confirm whether it is valid. The checker accepts standard UUIDs, no-hyphen UUIDs, UUIDs with braces, and URN-style UUIDs.

For UUID v7, the checker also shows the embedded timestamp. This is useful when you need to inspect an ID from logs, events, database rows, or debugging output.

Practical examples

• Database seed data: generate 50 UUIDs as SQL values and paste them into an insert script.
• API testing: generate UUIDs as a JSON array for mock requests or test payloads.
• Spreadsheets: generate one UUID per line and paste the list into a column.
• Logs and events: use UUID v7 when sorting by approximate creation time is useful.
• Public IDs: use UUID v4 when you want random identifiers that do not expose time information.

Tips for choosing the right UUID

Choose UUID v4 for the simplest and most private default. Choose UUID v7 when insert order, log order, or database sorting matters. Use standard lowercase UUIDs unless your system specifically requires uppercase, no hyphens, braces, or URN format.

For most real projects, the best starting choice is UUID v4 in standard lowercase format. For newer database-heavy systems where creation order matters, test UUID v7.

Sources

This tool is based on the current UUID specification and browser cryptography APIs used to generate secure random values.

• RFC 9562: Universally Unique IDentifiers (UUIDs) – the current official UUID standard, including UUID v4 and UUID v7.
• MDN Web Docs: Crypto.randomUUID() – browser API for generating cryptographically secure UUID v4 values.
• MDN Web Docs: Crypto.getRandomValues() – browser API used for cryptographically strong random bytes in the fallback generator.

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