How to Calculate a Tip Quickly and Exactly

Working out a tip should not take longer than eating the meal. With one shortcut and a little practice, you can get close in your head, and a calculator gives you the exact figure when you want it.

The 10% shortcut

Move the decimal point one place to the left. On a bill of $84.50, 10% is $8.45. Every other common tip is built from that number.

• 15%: take 10% and add half of it. $8.45 + $4.225 = $12.675, which rounds to $12.68.
• 20%: double the 10% figure. $8.45 × 2 = $16.90.
• 18%: take 20% and subtract one tenth of it ($16.90 − $1.69), or use 10% plus 8%. On this bill it is $15.21.

The exact formula

The tip is the bill multiplied by the tip rate written as a decimal.

Tip = bill × (percentage ÷ 100)

The total is the bill plus the tip. For an $84.50 bill with a 20% tip, the tip is $16.90 and the total is $101.40.

Tip before tax or after tax?

Both are common. Many people tip on the pre-tax subtotal, because sales tax is not part of the service. Others tip on the total because it is easier. If your bill shows the tax separately, using the subtotal gives a slightly lower tip, so pick the habit you are comfortable with and use it every time.

Splitting the bill

To split a bill evenly, add the tip to the bill and divide by the number of people. Three people sharing the $101.40 total each pay $33.80. Money is paid in whole cents, so some totals do not divide evenly. When that happens, one or two people pay a cent more so that the shares add up to the exact total.

How much should you tip?

In the United States, 15% to 20% is a common range for table service, and customs differ for other services and in other countries. A service charge that is already on the bill may be meant to replace the tip, so check your bill first.

Skip the mental maths

When you want the exact amount, or you are splitting a bill between friends, use our tip calculator. It works out the tip, the total, and each person’s share to the cent.