5 min read · Free educational guide
Basic tip formula
Tip amount = bill × (tip percent ÷ 100). Total = bill + tip. For an 18% tip on a $64.50 bill: 0.18 × 64.50 = $11.61 tip, total $76.11.
If you split evenly among people: each person pays total ÷ number of people (or tip ÷ people if you only split the gratuity).
Common tip percentages
Customs vary by country and service type. In many US restaurants, 15% is a baseline, 18–20% is common for good service, and 20%+ for excellent service. Cafés, delivery apps, and taxis may suggest different defaults.
When traveling, check local norms — in some places service is included, and an extra tip is optional or unusual.
Pre-tax or post-tax bill?
Many people tip on the pre-tax subtotal; others tip on the full amount including tax. Either approach is widely used. Pick one rule and stay consistent so group bills stay fair.
Mental math shortcuts
For 10%: move the decimal one place ($64.50 → $6.45). For 20%: double the 10% amount. For 15%: 10% + half of 10%. For 18%: 20% minus a little, or 10% + 5% + 3% if you prefer steps.
Use the free tip calculator
PercentBox’s tip calculator applies the same formulas, supports quick percent buttons, and can split the bill so everyone sees the same numbers.
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FAQ
- How much is a 20% tip on $50?
- $10 tip; $60 total. 20% is one-fifth of the bill.
- Should I tip on delivery fees?
- Policies and etiquette vary by app and region. Many people tip on the food subtotal; follow the app prompts and local custom.