➗ PHP Integer Division with intdiv() – Full Guide & Examples

🧲 Introduction – Why Integer Division Matters

In many applications — such as pagination, even distribution, or splitting tasks — you may want to divide numbers and discard the decimal. This is where PHP’s intdiv() function comes in handy.

Instead of using regular division (/), which returns a float, intdiv() performs mathematical integer division, returning the result as an integer.

🎯 In this guide, you’ll learn:

• What intdiv() is and how it works
• The difference between /, %, and intdiv()
• Examples with output and best practices

📘 What is intdiv() in PHP?

The intdiv() function divides two numbers and returns only the integer part of the result, discarding any remainder.

✅ Introduced in PHP 7.0

✅ Syntax:

intdiv(int $numerator, int $divisor): int

🧪 Practical Examples with Explanation

🔹 1. Basic Integer Division

echo intdiv(10, 3);  // Output: 3

📘 Explanation:
10 ÷ 3 = 3.33 → intdiv() drops the decimal → returns 3

🔹 2. Negative Values

echo intdiv(-10, 3); // Output: -3

📘 Explanation:
Result follows the sign of the numerator, rounding toward zero.

🔹 3. Division by 1

echo intdiv(99, 1);  // Output: 99

📘 Explanation:
Anything divided by 1 returns the number itself — remains an integer.

🔹 4. Division by 0

echo intdiv(10, 0);  // Error!

📛 Error: DivisionByZeroError
Unlike regular / division (which returns INF for floats), intdiv() throws an exception.

🔁 intdiv() vs / vs %

🧠 Best Practices

• ✅ Use intdiv() when you want integer-only results
• ✅ Avoid floating-point math when precision matters
• ❌ Don’t use intdiv() with zero or non-integer types
• ✅ Handle exceptions if divisor may be zero

📌 Summary – Recap & Next Steps

intdiv() is a fast and accurate way to divide integers when you don’t want fractions. It eliminates the need to cast or round float values and avoids floating point inaccuracies.

🔍 Key Takeaways:

• intdiv(a, b) returns the integer quotient of a ÷ b
• Safer and cleaner than casting or floor operations
• Avoid dividing by zero — it will throw an error

⚙️ Real-World Relevance:
Used in pagination, evenly distributing resources, tax calculations, statistical buckets, and financial systems.

❓ Frequently Asked Questions (FAQs)

❓ What does intdiv() do in PHP?
✅ It divides two integers and returns only the integer part (no decimals).

❓ Is intdiv() faster than type casting?
✅ Yes. It’s optimized for performance and is more precise than using (int)($a / $b).

❓ Can I use intdiv() with floats?
❌ No. Both arguments must be integers.

❓ What happens if the divisor is 0?
❌ A DivisionByZeroError is thrown — you must handle it.