You need an ID right now, not a library

You are scaffolding a prototype and every row needs a primary key. Or you want to confirm a downloaded file was not corrupted. Reaching for a random library, or worse, a website that "generates" the value for you, adds risk and friction to a two-second task.

UUIDs on demand

Open the UUID Generator and produce one or many RFC-4122 v4 identifiers using the browser's crypto-grade random source. Batch them for seed data, copy straight into your schema, and move on.

Hashes without a script

For a quick integrity check or a stable cache key, the Hash Generator computes MD5, SHA-1, SHA-256, or SHA-512 locally with the Web Crypto API. Paste the text, read the digest, and compare it to the value you were given — all in the browser, nothing uploaded.

Where this earns its keep

Seed fixtures and test rows with realistic unique keys.
Verify a file or payload matches an expected hash before trusting it.
Build cache-busting keys without leaving the page you are working in.

Both tools run entirely on-device, so the values you generate never pass through a server — handy precisely when the data is still rough and sensitive.

Frequently Asked Questions

Which is better for a primary key, a UUID or a counter?

It depends on ordering. A random identifier needs no coordination and is safe to generate anywhere, but it does not cluster in an index. A sequential value is friendlier to storage and worse for distributed generation.

Can two generated UUIDs collide?

In practice the random space is large enough that accidental collisions are not a concern. That is the entire point of generating locally without a central authority handing out the next number.

Should I hash a password with these tools?

No. Fast hashes are the wrong primitive for credentials, because speed is what makes them cheap to attack at scale. Use a deliberately slow, salted algorithm designed for passwords instead.

Generate UUIDs and hashes locally for prototypes