generator

UUID Generator Online 日本語ツール

日本語で使える uuid generator ツール: Generate random UUID v4 values online, copy batches, format IDs, and inspect existing UUIDs locally in your browser.

UUID を生成すると結果が表示されます。

有効

UUID を生成すると結果が表示されます。

UUID Course 日本語ガイド

日本語の uuid ガイド: Learn how UUIDs work, when to use v4, how formats differ, and what version and variant mean.

コースホーム

このツールについて

DevCove UUID Generator creates cryptographically random UUID v4 identifiers in your browser using the Web Crypto API. Generate one ID or a batch, switch between canonical, uppercase, compact, braced, and URN formats, copy individual values or the whole list, and inspect existing UUIDs to verify their version, variant, and normalized form.

使い方

Use this UUID generator when you need unique IDs for fixtures, database rows, API examples, tests, or local development.

  1. Choose Generate to create UUID v4 values locally in your browser.
  2. Set Count from 1 to 100 depending on how many IDs you need.
  3. Choose the output format: canonical lowercase, uppercase, no hyphens, braces, or URN.
  4. Click Generate to refresh the batch, Copy on one row for a single ID, or Copy all for a newline-separated list.
  5. Switch to Inspect when you want to validate a UUID copied from logs, a database, or an API response.
  6. Review the normalized value, detected version, variant, and input format before using the ID in code.

機能

Built for practical UUID workflows where speed, clarity, and local generation matter:

  • UUID v4 generation using browser cryptographic randomness.
  • Batch generation from 1 to 100 values with instant refresh.
  • Canonical lowercase UUIDs plus uppercase, compact, braced, and URN output formats.
  • Copy single UUIDs or the whole generated list.
  • Inspector for canonical, compact, braced, and urn:uuid values.
  • Version and variant detection, including RFC 4122 / RFC 9562 UUIDs.
  • Clear invalid-state messaging for malformed IDs.
  • 100% client-side processing—generated IDs and pasted IDs are not uploaded.

よくある質問

How do I generate a UUID online?

Open Generate mode, choose how many UUIDs you need, and click Generate. The values are created locally in your browser and can be copied one by one or as a batch.

What UUID version does this tool generate?

It generates UUID v4 values. UUID v4 uses random bits plus required version and variant bits, making it a good default for fixtures, client-side IDs, and general application identifiers.

Are generated UUIDs sent to a server?

No. Generation uses the browser Web Crypto API and runs locally. DevCove does not upload or store generated UUIDs or inspected values.

Can I generate many UUIDs at once?

Yes. Use the Count control to generate between 1 and 100 UUIDs, then copy individual rows or copy the entire batch as newline-separated text.

What is the canonical UUID format?

Canonical UUIDs use lowercase hexadecimal characters in the 8-4-4-4-12 hyphenated layout, for example 550e8400-e29b-41d4-a716-446655440000.

Can this validate UUIDs from logs or databases?

Yes. Inspect mode accepts canonical UUIDs, compact 32-character UUIDs, braced UUIDs, and urn:uuid values, then reports the normalized value, version, variant, and detected input format.