Random String Generator
Batch-generate random strings your way.
Runs entirely in your browser — nothing you enter is uploaded or sent to a server.
These strings are unpredictable, but they aren't a drop-in for a real password or cryptographic key that needs a specific format — set the length and character sets to match what you actually need. Read our full disclaimer.
About this tool
A flexible random-string generator for test data, tokens, sample IDs, coupon codes, and fixtures. Choose how many strings you want and how long each should be, then toggle which character sets to draw from — lowercase, uppercase, digits, and symbols. Every string is built with your browser's cryptographically secure random number generator (Web Crypto), so the values are unpredictable.
Handy for
Seed data and fixtures, coupon or invite codes, temporary keys, and placeholder identifiers — e.g. 20 strings of length 12 using letters and numbers.
How to use
- 1Set how many strings you want and the length of each.
- 2Toggle the character sets to include (lowercase, uppercase, numbers, symbols).
- 3Press Generate to create a fresh batch.
- 4Copy any single string, or use Copy all to grab the whole list.
Features
- Generate a whole batch at once, each a chosen length.
- Mix lowercase, uppercase, numbers, and symbols however you like.
- Every string drawn from the Web Crypto RNG, so values are unpredictable.
- Copy a single string or grab the entire batch.
Frequently asked questions
Are the strings truly random?
They're generated with crypto.getRandomValues, your browser's cryptographically strong random number generator, so they're suitable wherever unpredictable values matter.
Can I generate strings with only letters, or only numbers?
Yes — toggle the character sets you want. Turn everything off except numbers for a numeric code, or keep only letters for a readable token. At least one set has to be on.
Will the strings be unique?
Each string is drawn independently at random, so at a reasonable length repeats are extremely unlikely — but not formally guaranteed. If you need identifiers that are guaranteed unique, use our UUID Generator.
Can I use these as passwords?
The randomness is strong enough, but this tool is built for batches of generic strings. For a single account password with a strength estimate and a guaranteed character mix, use our Password Generator.
How is this different from the Password Generator?
The Password Generator makes one strong password at a time with a strength estimate. This tool makes a whole batch of random strings at once — handy for test data, codes, and IDs.
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