What is a custom alphabet?
A custom alphabet is the set of characters from which the generated random string may be built.
Security
Secure Random String Generator
Generate cryptographically secure random strings with custom length and character sets.
Tool
Secure Random String Generator
Generate cryptographically secure random strings with custom length and character sets.
This tool runs in your browser. Your input is processed locally and is not uploaded.
About this Tool
Use this secure random string generator for temporary secrets, identifiers and test data. Select the allowed characters and length while avoiding biased random selection.
Examples
- Generate a 24-character alphanumeric string
- Generate a numeric random string
- Generate a string from a custom alphabet
Frequently Asked Questions
How is random bias avoided?
Secure implementations reject random values that would create uneven character probabilities instead of using simple modulo reduction.
Can I exclude confusing characters?
Yes. Characters such as zero, uppercase O, lowercase l and uppercase I can be removed from the alphabet.
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