Work out sale prices, savings, tips, and per-person splits in one pass.
It chains together the three little calculations that always seem to come up at the same moment. First the discount: the original price is reduced by your percentage off, showing both the sale price and what you saved. Then the tip: your chosen percentage is applied to the discounted amount. Finally the split: the grand total is divided evenly between however many people are paying.
A $120 dinner with a 20% voucher becomes $96 (saving $24). An 18% tip on the $96 adds $17.28, for a total of $113.28 — or $37.76 each between three people. Doing that chain in your head at the table is exactly the kind of thing that goes wrong after dessert.
Typical US restaurant tips run 15–20% (18% is a common default), while many other countries tip modestly or include service in the bill. One point of etiquette debate the calculator sidesteps for you: some people tip on the pre-discount amount when using a voucher, reasoning the staff did the same work — if you prefer that, simply enter the original price with 0% discount to compute the tip, then apply your voucher separately.
After. The calculator tips on the discounted price, which is how card machines behave. If you prefer to tip on the original amount, run the tip calculation with 0% discount first, then note the discounted food cost separately.
Apply them in sequence: run the first discount, then enter the sale price as a new original price with the second percentage. Stacked percentages multiply rather than add — 30% then 20% off totals 44% off, not 50%.
Yes, informally — enter the tax percentage in the tip field to add it to a price. Just remember real receipts usually apply tax before tip, so for precision compute tax first, then rerun with the tip.