Free Random String Generator Online
Generate cryptographically random strings of any length and character set — passwords, tokens, API keys, and more.
How it works
Set length
Choose the string length (4–512 characters).
Choose character set
Pick from uppercase, lowercase, numbers, symbols — or combine them all.
Generate
Click Generate or press Enter. Uses crypto.getRandomValues() for cryptographic randomness.
Copy or download
Copy individual strings or download a batch as a text file.
Common use cases
Password generation
Create strong, random passwords with a mix of character types that meet most password policy requirements.
API keys and tokens
Generate random API keys, secret tokens, or CSRF tokens for authentication systems.
Test data
Generate random strings to seed test databases, mock user inputs, or populate fixture files.
Secret keys
Generate random secret keys for JWT signing, encryption, or HMAC operations.
Frequently asked questions
Is this cryptographically secure?
Yes. The generator uses crypto.getRandomValues() — the browser's CSPRNG (cryptographically secure pseudorandom number generator) — the same one used by crypto.randomUUID().
What is the maximum length?
This tool supports strings up to 512 characters. For longer strings, use the download option and generate multiple batches.
Can I generate multiple strings at once?
Yes — set the quantity field to generate up to 100 strings at once. Download them all as a .txt file.
Are my strings sent anywhere?
No. Everything runs in your browser using the Web Crypto API. Your strings are never transmitted.
What symbols are included?
The symbols set includes: ! @ # $ % ^ & * ( ) - _ + = [ ] { } | ; : , . ? — common characters supported by most systems.