About UUID Generator
UUID Generator emits cryptographically-random version 4 UUIDs (the standard random kind) and the newer version 7 UUIDs that embed a millisecond Unix timestamp at the start — perfect for primary keys you want naturally sortable by creation time. Generate one ID or up to 1000 in a single batch and export as plain text, JSON array, or CSV. Random bytes come from the browser's crypto.getRandomValues, which is a CSPRNG suitable for security tokens, session IDs and database keys. Nothing leaves the page.
- No uploads
- Browser-only
- Works offline
- 100% free
How it works
- 1
Choose v4 or v7
v4 is the classic fully-random UUID. v7 (RFC 9562) prepends a 48-bit Unix millisecond timestamp so the IDs sort by creation time — much better for database indexing.
- 2
Pick a count
Generate 1 to 1000 UUIDs in a single click. Re-roll the batch as many times as you want without leaving the page.
- 3
Export in your format
Copy as newline-separated text, a JSON array, or a single-column CSV — whichever your downstream tool expects.
Related tools
Browse allGenerate UUIDs, API keys, and random strings.
Cryptographically-strong passwords + strength checker.
Generate SHA-256, SHA-512, SHA-1, and SHA-384 hashes.
Generate fake names, emails, phones, addresses, dates for testing. Export JSON, CSV, or SQL INSERT.
Frequently asked questions
Are my files uploaded to a server?
No. Every tool on SnapToolz runs entirely inside your browser using JavaScript and WebAssembly. Your file is read locally, processed in memory, and the result is offered as a download. Nothing is sent to a server — there isn't one to send to.
When should I use v7 instead of v4?
Use v7 when your UUIDs become primary keys in a SQL database. Because v7 embeds the millisecond timestamp at the start, inserts append to the end of the index instead of fragmenting it — typically a 2–5x write speedup compared with random v4 keys. Use v4 when you specifically want IDs that leak no information about when they were created.
Are the v4 UUIDs cryptographically random?
Yes. They're generated from crypto.getRandomValues, the browser's CSPRNG, which on every modern OS is backed by the kernel entropy pool. The collision probability is the standard 1 in 2^122 — for context, you'd need to generate 1 billion UUIDs per second for ~85 years to have a 50% chance of a single collision.
Can I generate other UUID versions like v1 or v5?
v1 (MAC address + timestamp) leaks the machine's MAC and the exact creation time, so it's discouraged in modern systems. v5 (SHA-1 namespace) is occasionally useful for deterministic IDs derived from a name. Both are uncommon — if you have a real need, drop us a feature request and we'll add them.
Does it work offline?
Yes. SnapToolz is a Progressive Web App. After your first visit, the app is cached on your device and every tool keeps working without an internet connection.
Is SnapToolz free?
Yes — every tool is 100% free with no sign-up, no watermark, no hidden tier. The whole platform is open source and we have no plan to gate features.