About This Tool
Random String Generator independently selects characters from a deduplicated set. Use it for test data, temporary identifiers, or invitation codes. Length is measured in Unicode code points, so custom emoji work too. To require every selected character category, use Password Generator.
How to Use It
- Set the length of each string and the number of strings.
- Choose uppercase letters, lowercase letters, numbers, or symbols. Custom characters are added to the selected sets and deduplicated.
- Optionally exclude 0, O, o, 1, l, and I, then click Generate.
- Check the count and length, then copy all results or download random-strings.txt.
Examples
- Length 1, numbers only: each line contains exactly one digit from 0–9.
- Length 32, count 100: generate 100 lines, each with 32 Unicode code points.
- Turn off the built-in sets and enter ABC123 to use only those six characters.
Settings and Limits
Strings use secure randomness. Each string may contain 1–1024 code points, with 1–1000 strings per batch and a total limit of 262,144 code points. Custom input is limited to 8192 UTF-16 units and the combined set to 4096 code points. Line breaks and control characters are not allowed. An empty character set produces an error. Random generation does not guarantee that every string is unique.
Common Uses
- Create local test data and placeholder identifiers.
- Generate candidate invitation codes that are easy to read.
- Test how applications handle Unicode and long fields.
Privacy
Everything is generated locally in your browser. Inputs and results are neither uploaded nor automatically saved.
If you need to keep the results, copy or download them before leaving the page.
FAQ
How are random strings generated?
The tool uses secure randomness to build strings from your allowed characters. Each available character has the same chance of being selected.
Can I generate numbers only?
Yes. Select only the numbers set, or enter only digits as custom characters.
Can I exclude 0/O/1/l?
Yes. The look-alike filter applies to both built-in and custom character sets.
Can I use a random string as a password?
Security depends on its length, character set, and how it is used. For character-category requirements and guidance on the selection space, use Password Generator.
Does entering a character twice make it more likely?
No. The combined character set is deduplicated, giving each allowed Unicode code point the same chance of selection.