PHP Math

PHP math may sound like a pretty simple thing, but I assure you it's a set of tools that will totally change how you handle numbers in your projects.

You don't have to be the next Einstein in math, and it's far more than "add" and "subtract." They are robust, flexible, and handle just about any calculation you throw at them. Let's start with some basics, then get into some functions that will have you thinking, "Whoa, PHP can do that?"

Basic Arithmetic

Okay, let's start with the easy stuff. When you think of fundamental operations in arithmetic, I'm sure you're thinking of addition, subtraction, multiplication, and division. These are the things you've been doing since you first learned numbers, but now you're doing it with code in PHP.

It’s the beauty of it: in PHP, besides using a calculator or programming a simple script that does it for you, both can be done quite easily.

Want to add two numbers? Here's what that looks like:

$total = 5 + 10;
echo $total; // Outputs 15

Easy, right? Just replace the symbol (+, -, *, or /) based on what you're trying to achieve. Yet still, there's one key notation most programmers keep in mind: PHP does multiplication and division before addition and subtraction unless you've used parentheses.

It's just like PEMDAS all over again. But if you want to make your answer absolute, use parentheses to make your math super clear:

$result = (5 + 10) * 2;
echo $result; // Outputs 30

Now you're not just adding and multiplying; you're dictating how PHP sees the math. It's a minor detail, but it’s one that will save you a headache down the line.

Modulus - Finding What's Left Over

Here's a fun one you might not use every day, but when you need it, it’s a lifesaver: modulus (%). Modulus tells you the remainder when one number is divided by another. Think about it—this is perfect for checking if numbers are even or odd.

$number = 15;
echo $number % 2; // Outputs 1, meaning it's odd

If $number % 2 = 0, your number's even. If it's 1, it's odd. Why does that matter? Say you are coding something that needs to do every other something else. Modulus makes that kind of task much easier and tidier.

Exponents with pow() - Beyond Basic Math

If you want to raise a number to a particular power, PHP has just the thing for you: pow(). Suppose you want to square something or cube it. No problem.

Here's how you would raise 2 to the power of 3—so, 2^3:

echo pow(2, 3); // Prints out 8

Need to square something? You could use pow(), but seriously, if you're squaring, just multiply the number by itself. Sometimes, it's just easier:

$square = 4 * 4;
echo $square; // Outputs 16

Yep, that's all you need to know for exponents. Easy, right?

Square Roots - Going Back to Basics

Another super common calculation is square roots—especially if you're working with distances or areas. PHP's got a function, called sqrt(), for just this thing:

echo sqrt(16); // Output 4

But suppose you want a cube root or some other root. You can do this with pow() by just using a fraction:

echo pow(27, 1/3); // Outputs 3, which works out to be the cube root of 27

This trick keeps your code flexible because you can calculate all kinds of roots without having a special function for each one.

Rounding - Keeping Your Numbers Clean

Now, what if you've got a number like 4.6 and you need to clean it up? PHP gives you a few options here: round(), ceil(), and floor(). Here's what each does:

Let’s look at round():

echo round(4.6); // Outputs 5

If you want to make certain your number goes up no matter what, use ceil():

echo ceil(4.2); // Outputs 5

And for floor, i.e., rounding down, here's floor():

echo floor(4.9); // Outputs 4

That's ideal for cleaning up numbers, such as prices or scores, so they look nice.

Random Numbers

Random numbers are a bit exciting, aren't they? PHP's rand() function gives that to you, letting you create randomness in your code. Perfectly ideal for games, lotteries, and any feature in your application where you would want some surprise. Let's make it spit out a number between 1 and 10:

echo rand(1, 10); // Outputs a random number between 1 and 10

Just set the minimum and maximum, and PHP will choose a random number in that range.

Absolute Values - Going Positive

Sometimes you just want the positive version of a number, right? Perhaps you are dealing with distances, or you simply want to make a negative sign go away. That's what abs() is for:

echo abs(-10); // Outputs 10

Simple yet a lifesaver when you need only positive values.

Getting into Trigonometry

If you're working on a project that involves angles—say graphics or some kind of rotation—you’re going to be using PHP's sine, cosine, and tangent functions: sin(), cos(), and tan(). Fair warning: all of those take their input in radians, so you may want to convert from degrees using deg2rad():

echo sin(deg2rad(30)); // Outputs 0.5

This setup is pretty flexible for everything, from building something visual to getting into more complex calculations.

Min and Max - Finding Extremes

Need to find the highest or lowest number in a set? PHP's min() and max() functions make this easy:

$values = [3, 7, 10, 2];
echo min($values); // Outputs 2
echo max($values); // Outputs 10

Such functions come in handy when you want to do quick comparisons of numbers.

Constants - Your Built-in Math Helpers

PHP already has some constants ready for use. Some of them are M_PI for pi (3.14159…) and M_E for Euler's number (2.718…). Rather than writing out the full value of pi every time, you can use M_PI, which keeps things accurate and easy to read:

echo M_PI; // Outputs 3.1415926535898

These constants are helpful for any scientific or geometric calculation where precision matters.

Logarithms and Exponentials - Going a Little Further

To do calculations that involve exponential growth or decay, you have log() for natural logarithms and exp() for exponentials. Want the natural log of 100? Here's how:

echo log(100); // Outputs about 4.605

Want to raise e to a power? Try exp():

echo exp(1); // Outputs e, approximately 2.718

Ideal for financial or scientific calculations.

Hypotenuse - The Pythagorean Shortcut

Need to calculate the hypotenuse? PHP's hypot() makes it easy as pie:

echo hypot(3, 4); // Outputs 5

This will be a perfect shortcut for distance calculations, especially when working with grids or maps.

Wrapping Up

PHP features a great number of math functions beyond basic addition, subtraction, multiplication, and division—it's more like a toolkit for computation. From simple things like addition to somewhat more advanced functions, such as exponentials, square roots, and trigonometric functions, PHP offers you full power over everything that involves numbers.

Whether you need to round numbers to clean up prices, generate random values for a game, or use constants for precision, these functions will help you save time and strengthen your code. Once you get used to them, it’s like second nature—even the most complex math seems trivial.

So dive in, experiment a bit, and let PHP's math functions do the heavy lifting. You might be surprised at what you are able to do with just a few lines of code.