Count Prime Numbers in Range

Count how many prime numbers appear in a given inclusive range.

PythonBeginner
Python
# Program to count prime numbers in a range

start = int(input("Enter start of range: "))
end = int(input("Enter end of range: "))

count = 0
for num in range(start, end + 1):
    if num < 2:
        continue
    is_prime = True
    for i in range(2, int(num ** 0.5) + 1):
        if num % i == 0:
            is_prime = False
            break
    if is_prime:
        count += 1

print(f"Number of primes between {start} and {end} is {count}")

Output

Enter start of range: 1
Enter end of range: 10
Number of primes between 1 and 10 is 4

We reuse the primality test logic but increment a counter instead of printing each prime.