Generate random UUIDs (version 4) in bulk — up to 100 at a time — with one click to copy the whole list. UUID v4 takes 122 bits of randomness from the browser's cryptographic generator, making collisions practically impossible.
UUIDs are the standard way to give records, files, and API objects an identifier that is unique without any central coordination.
Frequently asked questions
What does v4 mean?
Version 4 UUIDs are fully random (122 random bits), as opposed to v1 which is based on time and MAC address.
Can two generated UUIDs collide?
The chance is astronomically small — you would need to generate billions per year for eons to expect one.
Are UUIDs uppercase or lowercase?
The standard writes them lowercase; the hex digits are case-insensitive in practice.
中文说明
批量生成随机 UUID（版本 4），一次最多 100 个，一键复制整列。UUID v4 的 122 位随机性来自浏览器的密码学随机源，碰撞概率实际上为零。
UUID 是给记录、文件和 API 对象赋予"无需中央协调即可保证唯一"的标识符的标准方案。
常见问题
v4 是什么意思？
版本 4 的 UUID 完全随机（122 个随机位），不同于基于时间和 MAC 地址的 v1。
两个 UUID 可能重复吗？
概率小到可以忽略——需要以每年数十亿个的速度连续生成无数年才可能遇到一次。
UUID 用大写还是小写？
标准写法是小写；不过十六进制数字在实际中大小写不敏感。