While loops

Basic while

while runs the body as long as the condition is True. Update the condition inside the loop or it will run forever.

n = 0
while n < 3:
    print(n)
    n = n + 1

break and continue

Use break to exit early and continue to skip to the next iteration.

n = 0
while True:
    if n == 3:
        break
    print(n)
    n += 1

Try it yourself

Run the example below. Edit it and see what changes.

count = 3
while count > 0:
    print(count)
    count -= 1
print("Go!")
 

Common mistakes

• ⚠Forgetting to update the loop variable, causing an infinite loop.
• ⚠Using a condition that is never True so the loop never runs.