Loops in Java

Repeat code with for and while loops, and count up, down and by steps.

🎯 What you will learn

Java’s for loop packs three things into one line: where to start, when to stop, and how to step. Once it clicks, you can count anything! 🔁

1. 🔁 for loop parts

for (start; keep-going check; step) { … }

for (int i = 1; i <= 5; i++) {
    System.out.println("Lap " + i);
}

2. ⬇️ Counting down

Use i– to count backwards.

for (int i = 3; i >= 1; i--) {
    System.out.println(i);
}
System.out.println("Liftoff! 🚀");

3. ⏳ while

Repeat while something is true.

int coins = 0;
while (coins < 50) {
    coins += 20;
}
System.out.println("Coins: " + coins);

Read the code, guess what it prints, then press 👀 Show output.

int n = 7;
for (int i = 1; i <= 5; i++) {
    System.out.println(n + " x " + i + " = " + (n * i));
}

int sum = 0;
for (int i = 1; i <= 10; i++) {
    sum += i;
}
System.out.println(sum);

Tap a card to flip it over!

How many stars print? Predict, then check.

for (int i = 0; i < 4; i++) {
    System.out.print("⭐");
}