Random String & Number Generator
Create random strings or numbers in bulk for test data, sample IDs or raffle numbers. Pick character types or use only your own characters, or draw integers from a range without repeats. For passwords use the Password Generator; for unique IDs use the UUID Generator.
🔒 Runs in your browser · Your data is never sent to a server
How to use
- Choose a type: random string, random integer or random decimal.
- For strings, pick the characters and length; for numbers, enter the minimum and maximum. Then set how many.
- Press "Generate" to list the results, one per line. Each press gives a fresh result.
- Use "Copy result" to copy everything as newline-separated text.
Notes
- Values come from your browser’s cryptographic generator (crypto.getRandomValues) without bias. Even so, do not use these results as passwords or encryption keys; use a dedicated password generator for that.
- You can generate up to 1,000 items at a time, and strings up to 256 characters long.
- Hiragana and katakana each cover the 71 basic and voiced/semi-voiced kana (no small kana, ゐ, ゑ or ヴ). Kanji can come from the 1,026 kyoiku kanji taught in Japanese elementary schools, or the 2,136 joyo kanji (which include them). Random kanji sequences do not necessarily form meaningful words.
- The width of an integer or decimal range (maximum − minimum) must be within about 4.29 billion (2^32), and decimals are limited to 6 places. Decimals are chosen uniformly in steps of the chosen precision, and both ends of the range can appear.
- "No duplicates" means the generated strings, or the drawn numbers, differ from each other (a string may still repeat a character inside itself).
- Your settings and results are processed only in your browser and never sent to a server.
FAQ
How is this different from the Password Generator?
This tool is for producing lots of random values: test data, sample IDs, raffle numbers. You can use only your own characters, draw integers or decimals from a range, or pick numbers with no repeats, up to 1,000 at a time. For passwords and keys, use the Password Generator, which also shows a strength estimate.
Are the generated values unpredictable?
They come from your browser’s cryptographic generator (crypto.getRandomValues), with re-draws so the ends of a range are not favored. Predictable generators such as Math.random() are not used.
What does "No duplicates" apply to?
For strings, it means no two generated strings are identical. For integers, it means each number in the range is drawn at most once, like picking raffle numbers. A single string may still repeat a character inside itself.
Can I generate hiragana, katakana or kanji strings?
Yes. Under "Characters" you can choose hiragana (71), katakana (71), kyoiku kanji (1,026 taught in elementary school) and joyo kanji (2,136 in common use). When you combine several sets, every character in the combined set is equally likely. For kanji outside the joyo list, such as those used in names, type them into "Extra characters".
How are random decimals chosen?
One value is chosen uniformly from the steps of the chosen precision (for example 0.01 for two places). The minimum and maximum can both appear. If a range end does not fall on a step, such as 0.005, only the steps inside the range are used.
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