How do I open the calculator?

iPhone: find the Calculator app icon on your home screen. Android: look in the app drawer or say "OK Google, open calculator."

How do I calculate a tip?

Enter the bill total, tap the multiply button (x), type the tip percentage as a decimal (0.15 for 15 percent, 0.20 for 20 percent), tap equals (=). Add the result to the bill total.

How do I figure out a sale discount?

Enter the original price, tap multiply (x), type the amount you will pay as a decimal (0.70 for 30 percent off, 0.75 for 25 percent off), tap equals (=).

How do I split a bill?

Enter the total bill amount, tap divide (/), enter the number of people, tap equals (=). Each person pays that amount.

How do I use the percent button?

The percent button converts a number to its decimal form. Some calculators let you type "45 + 20 percent" to automatically add 20 percent to 45.

How do I use voice assistant instead?

Say "Hey Siri, what is 20 percent of 85?" or "OK Google, what is 156 divided by 4?" for hands-free calculations — no app needed.

TekSure — Free Tech Help for Beginners & Seniors

Your phone has a built-in calculator that is more powerful than you might think. Beyond basic math, it can help you figure out tips at restaurants, calculate discounts while shopping, split bills with friends, and more.

On iPhone, the Calculator app has numbers on the bottom, basic operations on the right (plus, minus, multiply, divide), and clear/percent/plus-minus buttons at the top. Rotate your phone to landscape mode (sideways) to reveal a scientific calculator with advanced functions.

On Android, the Calculator app (or Google Calculator) works the same way. Some Android phones have it in the app drawer; you can also say "OK Google, open calculator" or search for "calculator" to find it.

Here are practical ways to use your calculator every day:

Calculating a tip: Enter the bill total, multiply by the tip percentage as a decimal. For a 20 percent tip on a $45 meal: type 45 x 0.20 = $9. For 15 percent: type 45 x 0.15 = $6.75. Add the tip to the total for your payment amount.

Figuring out a sale discount: If something is 30 percent off, multiply the price by 0.70 (which gives you the discounted price directly). For a $80 item at 30 percent off: type 80 x 0.70 = $56.

Splitting a bill: Add up the total, then divide by the number of people. For a $120 dinner with four people: type 120 / 4 = $30 each.

The calculator keeps your last answer on screen, so you can continue calculating without starting over. Tap "AC" (All Clear) or "C" (Clear) to start fresh. "C" clears the current number, while "AC" clears everything.

You can also ask Siri or Google Assistant to do math for you. Say "Hey Siri, what is 20 percent of 85?" or "OK Google, what is 156 divided by 4?" and get the answer without opening the app.