UUID (Universally Unique Identifier) is a 128-bit identifier that is unique across space and time. It's displayed as 32 hexadecimal digits in the format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. UUIDs are used in databases, distributed systems, and software development to uniquely identify records without central coordination.

What is the difference between UUID v1 and UUID v4?

UUID v1 uses timestamp and MAC address, making it time-ordered but potentially revealing hardware information. UUID v4 uses cryptographic random numbers, providing better privacy and unpredictability. For most applications, UUID v4 is recommended due to its randomness and security properties.

How do I generate multiple UUIDs at once?

Use the bulk generation feature: 1) Select UUID version (v1 or v4), 2) Enter the number of UUIDs you need (1-50), 3) Click Generate. All UUIDs will appear in a list. You can copy them individually or use "Copy All" to copy all UUIDs at once, one per line.

Are the generated UUIDs truly unique?

Yes, UUID v4 uses cryptographic random number generation (crypto.randomUUID()), making collisions astronomically unlikely. The probability of generating duplicate UUID v4 is approximately 1 in 2^122, which is effectively zero for practical purposes.

Is this UUID generator free?

Yes, this UUID generator is completely free with no limitations. Generate unlimited UUIDs, no registration required, and all generation happens in your browser for privacy and speed.

UUID生成器

一括生成サポート付きでUUID v1/v4を生成

設定

UUIDバージョンと個数を選択

バージョン

個数

結果

まだUUIDが生成されていません

生成ボタンをクリックしてUUIDを作成

UUIDとは？

UUID v4 (ランダム)

UUID v4は暗号学的ランダム性を使用してランダムに生成されます。ほとんどの場合に使用してください。

UUID v1 (タイムスタンプ)

UUID v1はタイムスタンプベースで、生成時刻を含みます。時系列で並べ替えができます。

ヒント

• UUID v4はランダムに生成され、最も一般的に使用されます

• UUID v1はタイムスタンプベースで、生成時刻順に並べ替えることができます

• UUIDをクリックするとクリップボードにコピーされます

• 'すべてコピー'を使用すると、すべてのUUIDを一度にコピーできます (1行に1つ)