🔤 Random String Generator
Generate random strings with custom length, character set, and pattern. Uses the Web Crypto API for cryptographically secure randomness — all in your browser, no upload, instant results.
About the Random String Generator
This random string generator runs entirely in your browser. Choose your length, count, character set, and an optional prefix, then click Generate to produce one or more random strings. Nothing is uploaded to a server — generation happens instantly with JavaScript on your device using the Web Crypto API.
Options explained
- Length — How many characters each generated string should contain (1–1000).
- How many — How many independent strings to generate at once (1–100).
- Prefix — Optional text prepended to every generated string. Useful for IDs like
user_a3F9k2. - lowercase / UPPERCASE / Numbers / Symbols — Toggle which character groups may appear. At least one must be selected.
- Exclude ambiguous — Removes
0 O l 1 Ifrom the pool so generated strings are easier to read and type by hand.
How to use the generator
- Set length, count, and (optionally) a prefix.
- Pick the character sets you want included.
- Click Generate — the strings appear in the output box, one per line.
- Click Copy All to copy all of them to your clipboard, or Clear to start over.
Frequently asked questions
Is the randomness secure enough for passwords or tokens? Yes. The generator uses crypto.getRandomValues(), the same API used for cryptographic operations in modern browsers. The output is suitable for passwords, API tokens, and session identifiers.
Does this tool upload my strings? No. All generation happens locally in your browser. Nothing ever leaves your device.
Why do I see duplicate characters next to each other? Each character is sampled independently from the pool, so duplicates can occur. This is normal and does not reduce security.
Is there a length limit? Each string can be up to 1000 characters, and you can generate up to 100 at a time. Going much higher may slow down your browser.