Prime Number Checker
One entry per line - check primality, list primes in a range, or find the Nth prime
Mode:
Max results:
Separator:
Calculation Result
Download CSV
| No. | Value | Result | Detail |
|---|
Introduction to the tool and how to use it
Prime checker and generator: one input box handles three common needs, one entry per line, many lines at once.
Composite numbers show their smallest prime factor (for example 360 = 2 × 180), while primes are marked yes. Large integers use BigInt plus Miller-Rabin (deterministic below 2^64), so no floating-point error; range mode uses the Sieve of Eratosthenes and returns instantly up to 5 000 000.
Composite numbers show their smallest prime factor (for example 360 = 2 × 180), while primes are marked yes. Large integers use BigInt plus Miller-Rabin (deterministic below 2^64), so no floating-point error; range mode uses the Sieve of Eratosthenes and returns instantly up to 5 000 000.
How to use
- Choose a mode:
· Check primality: one integer per line, such as97;
· Generate a prime list: one range per line, such as100,200;
· Nth prime: one index per line, such as1000. - Click start calculation; the result table shows the verdict, prime count, or the Nth prime.
- Results can be copied with one click and exported as CSV.
Prime test
Primes between 2 and 100
Between 2 and 100 there are 25 primes, from 2 up to 97.
- Range2 ~ 100
- Divisors25
- Smallest prime in range2
- Largest prime in range97
Primes in range
| # | Prime |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 11 |
| 6 | 13 |
| 7 | 17 |
| 8 | 19 |
| 9 | 23 |
| 10 | 29 |
| 11 | 31 |
| 12 | 37 |
| 13 | 41 |
| 14 | 43 |
| 15 | 47 |
| 16 | 53 |
| 17 | 59 |
| 18 | 61 |
| 19 | 67 |
| 20 | 71 |
| 21 | 73 |
| 22 | 79 |
| 23 | 83 |
| 24 | 89 |
| 25 | 97 |
- Large numbers are decided with Miller-Rabin (12 bases), which is deterministic below 2^64.
Common inputs
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