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UUID / ULID / Snowflake Generator

Generate UUID v1 / v4 / v7, ULID, NanoID, or Twitter Snowflake IDs — up to 10,000 at once. Cryptographically random, entirely in your browser, download as .txt.

  • 100% free
  • No signup
  • Runs in your browser
Common uses: uuid generator · uuid v4 generator · uuid v7 generator · ulid generator · nanoid generator

Used 18.0K times today

Random — standard choice for most apps

e.g. 550e8400-e29b-41d4-a716-446655440000

How to Use UUID / ULID / Snowflake Generator

  1. 1

    Pick an ID format

    UUID v4 (random) is the safe default. UUID v7 is time-ordered — best choice for database primary keys. ULID is sortable and URL-friendly. NanoID is short. Snowflake gives you a Twitter-style numeric ID.

  2. 2

    Set the quantity

    Generate 1 to 10,000 at a time. Use the 1 / 10 / 100 / 1000 quick-set buttons or type a custom count.

  3. 3

    Copy or download

    Click any row to copy one, "Copy All" for a newline-separated block, or "Download .txt" to save as a text file — handy for seeding databases.

Frequently Asked Questions

Which UUID version should I use for a database primary key?
For a NEW project, UUID v7 (RFC 9562) is the best default — it sorts by generation time so B-tree indexes stay compact and hot pages stay warm. UUID v4 is fine if you already use it everywhere, but its full randomness fragments the index. Avoid v1 in new code (leaks the MAC address).
What is a ULID and when should I choose it over UUID v7?
ULID is a 26-character Crockford base32 identifier — same time-ordering as UUID v7 but 10 chars shorter and more URL-friendly (no hyphens, no case-sensitive characters that visually confuse). Pick ULID for public-facing IDs; UUID v7 for internal DB keys where you want standard tooling support.
Are the IDs cryptographically secure?
Yes. All random bytes come from the browser's Web Crypto API (crypto.getRandomValues / crypto.randomUUID) — the same source used by TLS session keys. NanoID and ULID use the same source for their random portions.
What is a Snowflake ID?
A 64-bit sortable numeric ID pioneered by Twitter: 41 bits of Unix millisecond timestamp + 10 bits of machine ID + 12 bits of per-ms sequence. Fits in a bigint column and sorts chronologically. Used by Discord, Instagram, and most large distributed systems that need a smaller-than-UUID primary key.
Can I generate them offline?
Yes. Everything runs in the browser — no server, no telemetry, no analytics on the IDs themselves. Once the page has loaded once, the generator works fully offline.

Embed This Tool

Add this tool to your website for free. Just copy and paste the code below:

<iframe src="https://utilko.com/embed/uuid-generator/" width="100%" height="500" frameborder="0" title="UUID / ULID / Snowflake Generator"></iframe>

About UUID / ULID / Snowflake Generator

The UUID / ULID / Snowflake Generator creates every commonly used unique-identifier format used in modern backends: UUID v1 (timestamp + node), UUID v4 (fully random — the classic default), UUID v7 (time-ordered per RFC 9562 — the recommended default for database primary keys in new projects), ULID (26-char Crockford base32, sortable), NanoID (21-char URL-safe short IDs), and Twitter Snowflake (64-bit numeric IDs).

Generate 1 to 10,000 IDs in a single batch. Copy any single row, copy the entire list, or download as a .txt file ready to pipe into psql, redis-cli, a seed script, or a fixture generator. UUID output supports uppercase and no-hyphen variants for systems that require them.

Everything runs client-side with the Web Crypto API for cryptographic randomness. Nothing is sent to a server, nothing is logged, and the tool works fully offline once loaded — so you can safely generate IDs for production databases, seed data, correlation IDs, session tokens, or API keys without leaking them.

How to choose the right format

  • UUID v7 — new database primary keys, sortable audit logs, event IDs. Best default.
  • UUID v4 — existing systems already on v4, session tokens, correlation IDs.
  • ULID — user-facing IDs in URLs, event stream IDs, shorter alternative to UUID.
  • NanoID — short share codes, invite links, "not really an identifier" tokens.
  • Snowflake — high-throughput systems where 64-bit numeric IDs fit better than 128-bit UUIDs (BigInt column, JSON-safe as string).
  • UUID v1 — required by a legacy system. Otherwise, don't.

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