UUID Generator & GUID Generator — Free Online UUID v4, v7 & Validator

UUID Generator & GUID Generator — Free Online UUID v4, v7 & Validator. Free online UUID generator and GUID generator.

Create random UUID v4, time-ordered UUID v7, v1, v3, v5, NIL and MAX UUIDs in bulk, choose the format, and validate or decode any UUID — 100% in your browser. Our free online UUID generator creates universally unique identifiers the moment the page loads.

Pick a version — UUID v4 (122 random bits, the most common choice), UUID v7 (time-ordered, RFC 9562), v1 (timestamp + node), name-based v3 (MD5) and v5 (SHA-1), or the special NIL and MAX values — then generate UUIDs in bulk, up to 500 at a time.

The same tool is a full GUID generator: switch to uppercase or curly braces for Microsoft-style GUIDs, remove the hyphens for compact 32-character IDs, and output the list separated by new lines, commas, spaces or as a JSON array ready to paste into code, SQL seeds or test fixtures.

Need a quick random UUID or a new GUID? Press refresh and copy it with one click.

UUID v4 vs UUID v7: v4 is purely random and perfect for most identifiers, while v7 stores a 48-bit Unix millisecond timestamp in its first bits, so new IDs sort in creation order and keep B-tree indexes in PostgreSQL, MySQL and SQL Server compact.

UUID vs GUID: they are the same 128-bit format — Microsoft simply calls them GUIDs and often writes them in uppercase with curly braces.

For name-based IDs, choose v3 or v5, pick the DNS, URL, OID or X.500 namespace and enter a name to get the same deterministic UUID every time. Looking for other ID formats?

Try the ULID Generator for sortable Crockford-Base32 IDs, the Token Generator for random API keys and passwords, or the Hash Text tool for MD5 and SHA digests.

The built-in UUID validator and decoder accepts canonical, braced, urn:uuid: and hyphen-less input, shows the canonical form, the version and variant, and decodes the embedded timestamp of v1 and v7 UUIDs plus the clock sequence and node of v1 — handy as a GUID validator when debugging database rows or log entries.

All UUIDs are generated locally with the browser's cryptographically secure crypto.getRandomValues(), so nothing is sent to a server.

Download the list as a .txt or .json file, or share a link that re-opens the generator with the same version, quantity and format.

Frequently asked questions

How do I generate a random UUID or GUID?

Keep Version on v4 (the default) and a random UUID appears in the output box. Click Copy UUIDs to copy it or Refresh for a new one. A GUID is Microsoft's name for the same 128-bit identifier, so choose UPPERCASE or Braces under Format for a Windows-style GUID.

Should I use UUID v4 or UUID v7?

v4 is fully random (122 random bits) and the most common choice. v7 (RFC 9562) starts with a 48-bit millisecond timestamp followed by random bits, so new IDs sort in creation order, which keeps database indexes compact in PostgreSQL, MySQL and similar databases.

How do I generate UUIDs in bulk?

Set Quantity to any number from 1 to 500. Choose a Separator (New line, Comma, Space or JSON array) and a Format (lowercase, UPPERCASE or Braces), untick Hyphens for 32-character IDs, then click Copy UUIDs or download the list as .txt or .json.

How do v3 and v5 name-based UUIDs work?

The same namespace and name always produce the same UUID. Select v3 (MD5) or v5 (SHA-1), pick the DNS, URL, OID or X500 namespace or paste your own namespace UUID, and type the Name. v5 is generally preferred for new projects.

How do I validate or decode a UUID?

Paste it into the UUID Validator & Inspector field. It accepts canonical, braced, urn:uuid: and hyphen-less forms and shows whether it is valid, its version, variant and canonical form, plus the embedded timestamp for v1 and v7 and the clock sequence and node for v1.

Are the generated UUIDs private and unpredictable?

UUIDs are generated in your browser and never sent to a server. v4 and v7 use the browser's cryptographic random number generator. v1 is time-based rather than random, so avoid it for IDs that must be hard to guess.

How to use this online tool

UUID Generator & GUID Generator — Free Online UUID v4, v7 & Validator is designed for fast browser workflows when you need to format, validate, convert, decode, encode, generate, or inspect data without opening a heavy desktop app. Start with the input field or visible options, review the result, then copy or download the output for the next step.

Private processing in your browser

UUID Generator & GUID Generator — Free Online UUID v4, v7 & Validator keeps the normal processing step local in your browser. That is useful for code snippets, tokens, documents, configuration values, text samples, and other material that should not be sent to a remote service unless you explicitly choose to share it.

When this tool is useful

Use UUID Generator & GUID Generator — Free Online UUID v4, v7 & Validator for repeatable developer tasks, technical documentation, QA checks, quick conversions, debugging, content cleanup, and internal team workflows. The page focuses on clear inputs, immediate feedback, and output that is easy to reuse in code, reports, tickets, emails, or notes.

Practical tips

Before copying the final result, check important details such as spacing, casing, filenames, encoding, token structure, line breaks, or output format. Small checks prevent mistakes when the result is reused in source code, API requests, documentation, spreadsheets, or shared files.