How to Calculate a Tip (and Split the Bill)

A tip is a percentage of the bill, and the whole game is doing it quickly without a spreadsheet at the table. Multiply the bill by the tip percent and you're done. In the US, 15–20% of the pre-tax total is standard — 20% for good service, 15% at the low end. The tip calculator also splits the total per person, but the mental shortcuts below are usually all you need.

The fast way: start from 10%

Ten percent is the easiest number in math — just move the decimal one place left. On a $60 bill, 10% is $6. Everything else builds from there:

• 20% — double the 10%. $6 → $12.
• 15% — the 10% plus half of it. $6 + $3 = $9.
• 18% — 20% minus a little, or 15% plus a bit. Roughly $11 on $60.

Nobody minds a tip rounded to a clean number, so round up to the nearest dollar and move on.

Tip on the pre-tax or post-tax total?

Traditionally you tip on the pre-tax bill — the cost of the food and drink, before sales tax is added. In practice plenty of people just tip on the total because it's simpler and the difference is small. On a $60 bill with 8% tax ($4.80), tipping 20% on the pre-tax amount is $12 versus about $12.96 on the post-tax total — under a dollar apart. If you want to separate the two, the sales tax calculator pulls out the tax first.

Splitting the bill

To split evenly, add the tip to the bill, then divide by the number of people. A $60 bill plus a $12 tip is $72; across four people that's $18 each. If everyone had wildly different orders, split the tip proportionally to each person's share rather than evenly — the tip calculator can divide the total for you either way.

Worked example

A $85 dinner for three, tipping 20%:

• 10% of 85 = $8.50
• 20% = $17 tip
• Total: 85 + 17 = $102
• Per person: 102 ÷ 3 = $34 each

It's the same percentage skill behind the rest of our percentage and everyday math calculators. If the base move feels shaky, how to calculate a percentage covers it, and the percentage calculator handles any figure directly.

Frequently asked questions

How do I calculate a 20% tip?

Find 10% by moving the decimal one place left, then double it. On a $45 bill, 10% is $4.50, so a 20% tip is $9.

How much should I tip?

In the US, 15–20% of the pre-tax bill is standard for sit-down service — 20% for good service, 15% at the lower end. Norms vary by country, so adjust when travelling.

Do I tip on the total before or after tax?

Traditionally before tax, on the cost of the food and drink. Many people tip on the post-tax total for simplicity; the difference is usually well under a dollar.

How do I split a tip between people?

Add the tip to the bill, then divide by the number of people for an even split. For uneven orders, split the tip in proportion to what each person spent.

What's an easy way to work out 15%?

Take 10% (move the decimal left one place), then add half of that. On $80: 10% is $8, half is $4, so 15% is $12.