Tip Calculator: Gratuity and Splitting the Bill
A tip calculator applies a percentage to a bill, adds it to the total, and divides the result between however many people are paying. It removes the two things that slow a table down: the percentage and the split.
Tipping norms by country
- United States: 15-20% at restaurants is expected; servers are often paid a tipped minimum wage.
- Canada: 15-20%. UK: 10-12.5%, often already added as a service charge.
- Most of Europe: service is usually included; rounding up or 5-10% is generous.
- Japan, South Korea and China: tipping is not customary and can be declined.
Tip before or after tax
Tipping on the pre-tax subtotal is standard practice and is what most etiquette guides recommend. On a 100 bill with 8% tax, tipping 20% on the subtotal is 20 rather than 21.60. Also check whether a service charge is already on the bill — paying a percentage on top of an included charge is a common and avoidable double tip.
Mental shortcuts
Move the decimal one place left for 10%, halve that for 5%, and combine: 15% is 10% plus 5%, and 20% is 10% doubled. On a 68 bill that is 6.80 plus 3.40 for 15%, or 13.60 for 20%. Rounding up to the nearest whole unit per person makes the split cleaner and is almost always welcome.
Key takeaways — Tip Calculator
- Tip = bill × tip percentage; per person = (bill + tip) ÷ people.
- Tip on the pre-tax subtotal and check for an included service charge.
- Local custom varies widely — check before travelling.