How this works
Splitting a bill seems simple until somebody pulls out their phone's calculator and the table waits ten minutes. The mechanics: subtotal × tax_rate gives the tax, subtotal × tip_rate gives the tip (US norm — Europe and Asia generally tip on the post-tax total or a fixed % service charge). Total = subtotal + tax + tip. Per-person = total / N. The optional round-up adds a small amount to make each person's share end on a whole currency unit, which is convenient when paying in cash.
Tipping conventions you should know. **US**: 18–22% pre-tax is standard for sit-down service; 15% is the floor; 25%+ for excellent service. Tipping at delivery, takeout counter, and bars varies. **UK / Europe**: 10–12.5% for service that wasn't included; check whether "service charge" is already on the bill (often is in tourist areas). **Japan**: do not tip — it's genuinely awkward and may be refused. **Australia / NZ**: optional, 10% for excellent service. **Latin America**: 10% standard, often added automatically (called "propina" or "10%" line).
The calculator defaults to US pre-tax tipping because it's the most-googled style. If you're in a country where tip is calculated on the post-tax bill, multiply the tip rate by (1 + tax) — i.e. 18% post-tax ≈ 19.7% pre-tax at 9.5% combined sales tax. The math is small but adds up over time.
The formula
subtotal = pre-tax food + drink subtotal from the bill. tax_rate = local sales tax / VAT (e.g. 0.0875 for 8.75%). tip_rate = the percentage you want to leave (typically 0.18–0.22 in the US). N = number of people splitting equally. The calculator assumes equal split; for itemised splits, sum each person's items separately and re-run.
Example calculation
- $120 subtotal, 8.75% tax, 20% tip, 4 people, no round-up.
- Tax = $10.50. Tip = $24. Total = $154.50. Per person = $38.63.
Frequently asked questions
Should I tip on tax?
In the US: no — calculate tip on the pre-tax subtotal. The tip is for service, not for the government. In practice many people round up to the nearest dollar after applying tip on subtotal — that's fine. In countries where tip is on the post-tax total (UK, much of Europe), it's already baked in to the 10–12.5% norm.
How do I split when people ordered different things?
Tally each person's items into individual subtotals, then for each person: tax = subtotal × tax_rate, tip = subtotal × tip_rate, total = the sum. Most groups don't bother — they just split equally and let it average out across the meal. If someone had only a salad while others had steak and wine, an itemised split is fairer; otherwise even-split is the social default. This calculator does the even-split case; the itemised case is just N runs of the same calculation.
What if a service charge is already added?
Read the bill carefully. If it says "service charge included" or "service compris" or has a line for service already added (common in UK gastropubs, Italian restaurants, and many tourist areas worldwide), don't add additional tip — that would be double-tipping. If you want to add a small extra (5–10%) for excellent service on top of an included charge, that's your call but not expected. In the US, "tip suggestion" boxes on the receipt are just suggestions, not service charges — they're always optional.