Tip Calculator

How to use the tip calculator

1. Enter the bill total as printed on the check, including tax.
2. Enter the tax from the same check if you want to tip on the amount before tax. Leave it at 0 if you don’t know it or prefer to tip on the full total.
3. Pick a tip percentage with the chips or type any rate.
4. Enter the number of people splitting the bill, and choose whether each share should be exact or rounded up to the next dollar.

The results show the tip, the total with tip, each person’s share and the tip at a few other rates for comparison. The headline also shows the tip as a percentage of the amount it was figured on, which changes if you round up.

The tip formula

This is the basic percent equation, “amount is percent of base,” from the open textbook Prealgebra 2e from OpenStax. Its Example 6.20 is a tip: an 18% tip on a $68.50 restaurant bill is 0.18 × 68.50 = $12.33, for a total of $80.83. The calculator opens on that example.

The tip is rounded to the cent. If you split the bill, each share is rounded up to the next cent so the shares can’t come to less than the total. Three people splitting $100 each pay $33.34, and the extra two cents go to the server.

Tip before tax or after?

Tipping on the subtotal before tax means the tip reflects the food and service, not the tax rate where you happen to be eating. Tipping on the full total is simpler and gives a slightly larger tip. Either is a personal choice, and the difference is usually small.

For example, a check of $84.60 that includes $6.60 of tax has a pre-tax subtotal of $78.00. A 20% tip on the subtotal is $15.60. A 20% tip on the full $84.60 would be $16.92, or $1.32 more. With the switch on and the tax entered, the calculator tips on $78.00.

If a check shows a discount or a coupon, some people tip on the price before the discount, since the service was the same. Enter the pre-discount amount as the bill if that is your preference.

Splitting the bill

Even split. Enter the number of people. For the $84.60 check with a 20% pre-tax tip, the total is $100.20 and each of three people pays $33.40.

Rounding up. Paying in round numbers is easier with cash and avoids leftover cents. Rounding each share up to $34 brings the total to $102.00, which makes the tip $17.40, or 22.3% of the subtotal. The calculator shows the new tip and its percentage so you know what rounding costs.

Uneven split. When people ordered very different amounts, give each person their own share of tax and tip in proportion to what they ordered. On the same check, tax is 6.60 ÷ 78.00 = 8.46% of the subtotal. Someone whose items came to $30 pays 30 + (30 × 8.46%) + (30 × 20%) = 30 + 2.54 + 6.00 = $38.54. To do it here, enter $30 plus their share of the tax as the bill, their tax as the tax, and one person.

Tipping in your head

• 10%: move the decimal point one place left. 10% of $68.50 is $6.85.
• 20%: double the 10% figure: $13.70.
• 15%: 10% plus half of it: $6.85 + $3.43 = $10.28.
• 18%: 20% minus 2% (a fifth of the 10% figure): $13.70 − $1.37 = $12.33.
• 25%: divide by 4: $17.13.

Rounding the bill first makes this even quicker: $68.50 is about $70, and 20% of $70 is $14. The estimate is a little high, which most servers won’t mind.

Check the receipt before you tip

Some checks already include a service charge or an automatic gratuity, especially for large groups. That line is part of the bill total. If you want the tip you add to be the only gratuity, subtract the service charge first, or reduce your rate so the combined amount is what you intended.

Card terminals often suggest tip amounts. The percentages they show may be figured on the total after tax, or after a service charge, so the dollar amounts can differ from what you calculate here. Comparing the suggested dollar figure with the calculator’s tells you which base the terminal used.

The suggested rates on the chips are only shortcuts. Tipping customs differ between countries, regions and types of service, and the calculator doesn’t recommend a rate.

Quick reference: tips on common bills

• $20 bill: 15% = $3.00, 18% = $3.60, 20% = $4.00
• $45 bill: 15% = $6.75, 18% = $8.10, 20% = $9.00
• $60 bill: 15% = $9.00, 18% = $10.80, 20% = $12.00
• $85 bill: 15% = $12.75, 18% = $15.30, 20% = $17.00
• $120 bill: 15% = $18.00, 18% = $21.60, 20% = $24.00

For other amounts, the “other tip rates” line under the results does the same comparison for your bill.

Rounding the total instead of the tip

When you sign a card slip, it is often easier to pick a round total and let the tip be whatever makes up the difference. With the $68.50 check and an 18% tip, the exact total is $80.83. Rounding the total up to $81.00 makes the tip $12.50, which is 18.2% of the bill. Rounding up to $82.00 makes it $13.50, or 19.7%. Rounding the total rather than the tip keeps the arithmetic on the slip simple and makes it easy to check against your statement later.

Shared dishes in an uneven split

When a group shares some dishes and orders others separately, divide the shared items first. A $12 appetizer shared by three people adds $4 to each person’s subtotal. Then apply tax and tip to each subtotal as described above. Doing it in that order means everyone pays tax and tip on exactly what they ate, and the shares still add up to the full check plus the tip.

Sources & assumptions

How this calculator gets its numbers. Full method: our methodology.

• Tip = tip rate × the amount tipped on: the bill minus the tax you enter (if the before-tax option is on), or the full bill.
• The tip is rounded to the cent; split shares are rounded up to the cent, or to the next dollar if you choose.
• When shares are rounded up, the tip is recalculated as total − bill and shown as a percentage.
• Service charges are part of the bill you enter; the calculator doesn’t detect them.

Sources

1. OpenStax (Rice University), Prealgebra 2e, 6.2 Solve General Applications of Percent. “Amount is percent of base” and Examples 6.14–6.20 (35% of 90 = 31.5; 36 is 75% of 48; 6.5% of $18 = $1.17; 9 is 25% of 36; an 18% tip on $68.50), plus percent increase and decrease in Examples 6.23 ($26 to $36, 38.5%) and 6.24 ($3.71 to $3.64, 1.9%).

Last reviewed November 2, 2026. The rate chips are shortcuts, not recommendations; tipping customs vary by place and service.