Tipping math is just a percentage of the bill — and there's a quick mental shortcut so you never need to fumble at the table.
The 10% trick
Start by finding 10% of the bill: move the decimal one place left. On a $50 check, 10% is $5. From there:
- 20% — double the 10%. ($5 × 2 = $10.)
- 15% — take 10% plus half of it. ($5 + $2.50 = $7.50.)
- 18% — split the difference, a bit under 20%. (about $9.)
The Tip Calculator does this instantly and also splits the total across any number of people.
What percentage should you tip?
In the U.S., 18–20% is standard for good sit-down service, 15% for adequate service, and a dollar or two per drink at a bar. For takeout, tipping is optional and usually smaller. Tip on the pre-tax subtotal if you want to be precise, though many people just use the total for simplicity.
Splitting the bill
To split evenly, add the tip to the bill and divide by the number of people. For a $50 bill with a $10 tip across four people, that's $60 ÷ 4 = $15 each. If shares are uneven, total each person's items first, then apply the same tip percentage to each. The underlying skill is just percentages — the same math behind the Percentage Calculator and the Discount Calculator.