Random String Generator
Generate random alphanumeric strings of any length for IDs, tokens and test data.
Letters and digits only, from 4 to 128 characters
Every string uses the same 62 characters: A to Z, a to z and 0 to 9. There are no options for symbols or for a narrower alphabet. Choose the length with the slider (16 by default) and press Generate. A string appears when the page loads, but moving the slider doesn't replace it, so press the button after changing the length.
One run at the default length gave uc7IGLgHyvrBvIni. Each character is picked with crypto.getRandomValues, the browser's cryptographic random source, so strings can't be predicted from earlier ones.
Safe to drop almost anywhere
Because the output has no punctuation, it needs no escaping in the places where symbols cause trouble:
- URLs and query strings: nothing needs percent-encoding, so a string works as a share code or a short link slug.
- File and folder names: no slashes, colons or spaces, which keeps it valid on Windows, macOS and Linux.
- CSV, shell commands and config files: no commas, quotes or dollar signs to break a line or trigger a variable.
- Test data: fill a username, reference or SKU column with values that look realistic and never collide with real records.
Mixed case stops helping in case-insensitive systems
Some places treat Ab3x and AB3X as the same value: file names on default Windows and macOS drives, email addresses, domain names and many database text comparisons. There the 62-character alphabet effectively shrinks to 36, and two generated strings that differ only in case would clash.
| Length | Case-sensitive (62) | Case-insensitive (36) |
|---|---|---|
| 8 | 47.6 bits | 41.4 bits |
| 16 | 95.3 bits | 82.7 bits |
| 22 | 131.0 bits | 113.7 bits |
If the destination ignores case, either add a few characters or lowercase the string before you use it, so what you store is exactly what the system compares.
Codes people have to read or type
For a voucher printed on a card or a code read out over the phone, a fully random string has a drawback: it can contain 0 and O, or 1, l and I, side by side. This tool has no setting to leave them out. Keep such codes short, show them in a font that tells these characters apart, and accept either case on input where your system allows it.
Frequently asked questions
How long should a random ID be?+
For values that only need to be distinct in a test dataset, 8 to 12 characters is plenty. For anything guessable from outside, such as a private share link, 22 characters gives about 131 bits, comparable to a 128-bit token.
Can I include symbols?+
Not here. If you need punctuation, for example to meet a password rule, a password generator lets you add symbols to the pool.
Can I generate a list of strings at once?+
No, it produces one string per click. Press Generate repeatedly and copy each result, or generate in your code if you need thousands.
Should I use this for API keys?+
It is random enough, but a token generator that outputs hexadecimal is usually a better fit for keys, since hex survives case changes and copy-paste without ambiguity.
Embed this tool on your website
Free to use on blogs, school sites and intranets. Paste this code into your page's HTML; please keep the credit line.
<iframe src="https://utilityapp.lat/embed/dev/random-string-generator" title="Random String Generator" width="100%" height="600" style="border:0;max-width:760px" loading="lazy"></iframe> <p style="font-size:13px"><a href="https://utilityapp.lat/dev/random-string-generator">Random String Generator</a> by UtilityApp</p>