Tip on pre-tax vs post-tax — why the toggle exists#
In many places the customary tip is calculated on the food-and-drink subtotal before sales tax; elsewhere people tip on the full amount printed at the bottom of the check. Those are not the same number — on a $100 bill with 10% tax and 20% tip, tipping before tax yields a $20 tip and $130 total, while tipping after tax yields a $22 tip and $132 total. The gap grows with higher tax rates or larger checks, which is exactly why a single hard-coded assumption frustrates half the visitors. This calculator lets you pick either convention so the output matches how you (or your local custom) actually tip, instead of baking in one rule and hoping it fits.
Why “round tip up” ceilings the tip, not the total#
Rounding the tip up to the next whole currency unit is a common convenience when you want a clean cash tip or a simple mental check — for example, 15% of $47 is $7.05, which rounds up to $8. The total then becomes bill + tax + that rounded tip. Rounding the grand total instead would change the effective tip percentage in a less transparent way and make it harder to see what you actually left for service. This tool keeps the rounding on the tip line so you always know the gratuity amount, then derives totals and per-person shares from that rounded tip.
Splitting evenly is simple math — until tip and tax enter#
Dividing a bare subtotal by the number of people is easy; once tip and optional tax are included, each person’s fair share is (bill + tax + tip) ÷ people, and their tip share is tip ÷ people. Showing both matters when one person pays the card tip while others reimburse the rest, or when someone wants to cover only their portion of the gratuity. The calculator updates those figures instantly as you change party size, so you can try “what if three of us split?” without redoing the arithmetic by hand.
Presets vs custom tip percentages#
Ten, fifteen, eighteen, twenty, and twenty-five percent cover the most common restaurant ranges in one tap. Custom percentage is there for service charges already printed on the bill, cultural norms outside that band, or when you want an exact percentage that is not on the preset row — the math is the same either way. Presets simply save a few keystrokes; they do not change how tip base, tax timing, or round-up behave. If a receipt already lists an automatic gratuity, enter that percentage as custom so the split still matches the check.