Random String Generator
Build a random string from the character sets and length you choose.
This tool builds a random string from the characters you allow. Set the length, tick which character sets to draw from, and press Generate String for a fresh result you can copy. It is handy for placeholder IDs, sample data, test tokens and throwaway values. Generation runs entirely in your browser using JavaScript's built-in random function — nothing is sent to a server.
Length and character sets
The String Length field accepts 1 to 128 characters (it defaults to 12, and values outside that range are clamped back into it). Four toggles decide the alphabet: uppercase A–Z, lowercase a–z, digits 0–9, and a symbol set that includes !@#$%^&*() along with brackets and other punctuation. The first three are on by default and symbols are off. Each position in the string is picked at random from the combined pool, so turning a set on immediately widens the possible characters. If you untick every set, nothing can be generated and the tool asks you to choose at least one.
What the Strength and Composition labels mean
Two readouts sit under the result. Strength is based only on length — "Standard" up to 8 characters, "High" from 9 to 16, and "Extreme" beyond 16 — so it is a rough size cue rather than a true measure of unpredictability. Composition shows "Full Mix" once the combined character pool passes 50 characters and "Limited" below that. Treat both as quick indicators; they do not calculate real entropy or guarantee anything about how hard a string is to guess.
Fine for test data, not for real passwords
The random values come from the browser's ordinary Math.random(), which is not a cryptographically secure source. That is perfectly fine for mock records, sample keys, filler content and one-off identifiers. For anything that actually protects an account — passwords, secret keys, tokens — use a dedicated password manager or a generator built on a cryptographic random source, and never reuse a string produced here for that purpose.
Frequently Asked Questions
What is the longest string I can make?
128 characters. The minimum is 1 and the default is 12; if you type a number outside 1–128 it is pulled back to the nearest end of that range before generating.
Is this safe to use for passwords?
It is not recommended. Strings are produced with Math.random(), not a cryptographic generator, and the Strength label only reflects length. Use a proper password manager for credentials that matter.
Which symbols are included?
Ticking the symbol set adds common ASCII punctuation such as ! @ # $ % ^ & * ( ), plus brackets, slashes and other marks, expanding the pool well beyond letters and digits.
What happens if I turn every character set off?
Nothing will generate. The tool needs at least one set enabled and will prompt you to select one, because there would be no characters to draw from otherwise.