Random String Generator
Generate random strings, IDs and codes in bulk.
What does Random String Generator do?
Create random strings of any length from a character set you define — alphanumeric IDs, hex tokens, numeric codes or a fully custom alphabet. Useful for test fixtures, coupon codes and short identifiers.
How to Use Random String Generator
- 1Set the lengthHow many characters per string.
- 2Choose the alphabetA preset, or type your own characters.
- 3Set the quantityOne or many.
- 4Copy or downloadAll results at once.
Key Features
- Presets for alphanumeric, lowercase, hex, numeric and URL-safe alphabets
- Fully custom character set
- Generate up to 1,000 strings at once
- Optional prefix and suffix for structured IDs
- Entropy and collision-probability estimate for your chosen length
- Cryptographically secure randomness
Frequently Asked Questions
How long should a random ID be?
It depends on how many you will create. From a 62-character alphabet, 8 characters gives 47 bits — fine for a few million values. For anything database-scale, use 16 characters or a UUID. The collision estimate updates as you change the length.
What is a URL-safe alphabet?
Letters, digits, hyphen and underscore — characters that need no percent-encoding in a URL. Use it for anything that appears in a path or query string.
Can I use these as passwords?
Yes, they are generated from the same secure source. The password generator is better suited to it because it can guarantee a character from each set and shows a strength assessment.
Are the strings guaranteed unique?
No. Each is generated independently, so duplicates are possible in a large batch. The collision estimate tells you how likely that is; use a UUID if uniqueness must be guaranteed.
Values come from crypto.getRandomValues, your browser’s cryptographically secure random source, and are never transmitted or logged. Copy anything you need before closing the tab — it cannot be recovered.
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