Tipping percentages vary by service type, region, and quality of service, but the underlying calculation is always the same: a percentage of the bill, sometimes split across a group. Knowing standard ranges takes the guesswork out of a moment that shouldn't require mental math under pressure.
In the U.S., 15-20% is the standard range at full-service restaurants, with 18-20% typical for good service and higher (20-25%) sometimes offered for exceptional service. Some people calculate the tip on the pre-tax subtotal, others on the total after tax — there's no universal rule, but calculating on the subtotal is the more common convention.
How Tip and Total Are Calculated
Tip Amount = Bill × (Tip Percentage ÷ 100)
Total Bill = Bill + Tip Amount
Per-Person Amount (if splitting) = Total Bill ÷ Number of People
A Worked Example
A $180 group dinner bill, splitting a 20% tip among 4 people: Tip = 180 × 0.20 = $36. Total Bill = 180 + 36 = $216. Per-person share = 216 ÷ 4 = $54, including $9 of that being each person's share of the tip.
Common Mistakes to Avoid
- Tipping on the post-tax total when the norm is pre-tax subtotal: this is a small difference, but worth being consistent about, especially in high-tax areas where the gap is more noticeable.
- Forgetting to check if gratuity is already included: some restaurants (especially for large groups) automatically add an "included gratuity" line — check the bill before tipping again on top of it.
- Splitting unevenly among a group without accounting for different orders: an even split is simplest, but groups with very different order sizes sometimes prefer splitting based on what each person actually ordered.
- Undertipping for delivery or complex service: some service types (delivery in bad weather, large parties, complex custom orders) often warrant tipping toward the higher end of the standard range.
Bottom Line
Tipping is simple percentage math once you've settled on a rate. Use a Tip Calculator to instantly calculate the tip, total, and per-person split for any bill and group size.