Random String Generator
Generate random strings from any character set.
Random String Generator
Generate random strings from the characters you choose: lowercase and uppercase letters, digits, symbols, and any extra characters you type yourself. Make one string or thousands, with a fixed length or a random length between a minimum and maximum. It is a quick way to create test data, identifiers, coupon codes, filler content and random keys.
Build your own character set
Toggle the four built-in sets – a–z, A–Z, 0–9 and symbols – and add anything else in Extra characters: accented letters, emoji, underscores or a custom alphabet like ACGT. Turn on Exclude look-alikes to remove i, l, 1, L, o, 0 and O, so codes that people have to read or type are not misread.
Variable length strings
Many generators only produce fixed-length output. Here you can set a range, for example 3 to 30 characters, to stress-test form fields, database column limits, truncation logic and responsive layouts with realistic variation.
Unique results
With Unique strings enabled the generator never returns the same string twice in one batch. That matters for things like voucher codes or primary keys. If the requested count is larger than the number of possible strings – say 100 unique strings of length 1 from 10 digits – you get a clear error instead of an endless loop.
Security
Every character is picked with the Web Crypto API, so each position is independent and uniformly distributed. A 12-character string from letters and digits has about 71 bits of entropy, more than enough for most random identifiers. Generation happens entirely in your browser.
Looking for letters and digits only? Use the Random Alphanumeric Generator. For passwords with strength rules use the Password Generator.
Frequently Asked Questions
Can the strings have different lengths?
Yes. Set a different minimum and maximum length and every string gets its own random length in that range, which is useful for testing input validation and layout.
How do I add my own characters?
Type them into 'Extra characters'. They are added to the selected sets and duplicates are removed. To use only your characters, turn all four sets off and enter the full alphabet there, for example ACGT for DNA sequences.
Which symbols are included?
The symbol set is !@#$%^&*()-_=+[]{};:,.<>/?~. Characters that often cause escaping trouble, such as quotes, backslashes and backticks, are left out; add them through Extra characters if you need them.
Is this a password generator?
The strings are cryptographically random, so they can serve as passwords, but the Password Generator adds strength estimates and rules such as requiring at least one character of each type.