Random String Generator
Type the number of characters and get a random string of exactly that length — choose lowercase, uppercase, digits and symbols, exclude look-alike characters, and generate many at once. Uses your browser's crypto for strong randomness.
About this tool
A random string generator produces unpredictable sequences of characters that you can use as API keys, temporary passwords, test fixtures, database seeds, invite codes, or unique identifiers. Instead of mashing the keyboard and hoping for enough entropy, you type an exact length and get a clean string built from the character sets you choose.
This tool draws its randomness from your browser's Web Crypto API (crypto.getRandomValues) whenever it is available, which is far stronger than Math.random and suitable for security-sensitive values. You control lowercase, uppercase, digits, and symbols, can exclude look-alike characters, and can generate many strings in a single batch.
How to use
- Enter the length — the exact number of characters each string should have.
- Toggle the character sets you want: lowercase, uppercase, digits, and symbols.
- Enable "Exclude similar characters" to drop easily confused glyphs like l, 1, I, O, and 0.
- Set how many strings to generate if you need a batch rather than one.
- Read the generated strings in the output area.
- Copy a single string or the whole batch to your clipboard.
Features
- Cryptographically strong randomness via the browser's Web Crypto API, with a safe fallback when it is unavailable.
- Precise length control — you decide exactly how many characters each string contains.
- Mix and match lowercase, uppercase, digits, and symbols to satisfy any password or token policy.
- Optional exclusion of look-alike characters (l, 1, I, O, 0) to prevent transcription errors.
- Batch mode generates up to hundreds of strings at once for seeding tests or bulk codes.
- Everything runs locally in your browser, so generated secrets never touch a network.
Frequently asked questions
How random are the strings — can I use them for passwords or keys?
When your browser supports the Web Crypto API, the tool uses crypto.getRandomValues, which is designed for cryptographic use and is appropriate for passwords, tokens, and keys. It falls back to Math.random only if crypto is unavailable.
Are the generated strings sent anywhere?
No. Generation happens entirely in your browser and nothing is transmitted to a server. This makes it safe for creating secrets you never want to leave your device.
What does "exclude similar characters" do?
It removes glyphs that are easy to mistake for one another — lowercase L, the digit 1, uppercase I, uppercase O, and the digit 0 — so strings are easier to read aloud and type by hand.
Can I generate many strings at once?
Yes. Set the count field to produce a whole batch in one click, which is handy for seeding databases, creating test users, or issuing multiple invite codes.
What is the maximum length I can request?
Each string can be up to several thousand characters long, which covers everything from short PINs to long high-entropy keys.