How to Calculate a Tip
The formula, fast mental math shortcuts, and worked examples for any bill amount — so you can figure out the tip in seconds, with or without your phone.
Just need the number? Use the calculator.
Enter any bill amount and tip percentage — splits the bill too.
The tip formula
Every tip calculation comes down to one formula:
To get your total, add the tip to the bill: Total = Bill + Tip.
For a $48 bill with a 20% tip: $48 × (20 ÷ 100) = $48 × 0.20 = $9.60 tip. Total = $48 + $9.60 = $57.60.
That's the complete calculation. Everything below is about doing it faster, or in edge cases where there's a decision to make.
Step-by-step worked example
Say your restaurant bill comes to $63 and you want to leave a 20% tip.
- Find 10% by moving the decimal one place left: $63 → $6.30
- Double it to get 20%: $6.30 × 2 = $12.60
- Add to the bill: $63 + $12.60 = $75.60 total
That's the fastest mental math method for 20% — and it works for any bill amount. No multiplication required.
Quick tip reference table
Common bill amounts and tip amounts at the three most common percentages:
| Bill | 15% tip | 18% tip | 20% tip | 25% tip |
|---|---|---|---|---|
| $20 | $3.00 | $3.60 | $4.00 | $5.00 |
| $30 | $4.50 | $5.40 | $6.00 | $7.50 |
| $40 | $6.00 | $7.20 | $8.00 | $10.00 |
| $50 | $7.50 | $9.00 | $10.00 | $12.50 |
| $60 | $9.00 | $10.80 | $12.00 | $15.00 |
| $75 | $11.25 | $13.50 | $15.00 | $18.75 |
| $100 | $15.00 | $18.00 | $20.00 | $25.00 |
| $125 | $18.75 | $22.50 | $25.00 | $31.25 |
| $150 | $22.50 | $27.00 | $30.00 | $37.50 |
| $200 | $30.00 | $36.00 | $40.00 | $50.00 |
Mental math shortcuts for every percentage
You don't always need the formula. Here are fast shortcuts for the four most common tip percentages:
15% tip: Find 10% (move decimal left), then find 5% (half of 10%), then add them. On $44: 10% = $4.40, 5% = $2.20, total = $6.60.
18% tip: Find 20% (double the 10%), then subtract 10% of that. On $60: 20% = $12, subtract 10% of $12 = $1.20, so 18% = $10.80.
20% tip: Move the decimal left (10%), then double it. On $53: 10% = $5.30, doubled = $10.60.
25% tip: Find 10%, then multiply by 2.5. On $40: 10% = $4, × 2.5 = $10. Or find 20% and add half of that: $8 + $4 = $12. Both work.
Pre-tax vs. post-tax: which base do you tip on?
Etiquette guides — including Emily Post — recommend tipping on the pre-tax subtotal. The reasoning: sales tax goes to the government, not the restaurant or the server, so there's no reason the server's tip should include a share of it.
In practice, the difference is small enough that most people just tip on whatever number appears most prominently on the receipt. On a $60 bill with 9% tax, the tax is $5.40, making the post-tax total $65.40. A 20% tip on $60 is $12.00; on $65.40 it's $13.08. The server gets $1.08 more if you use the post-tax figure.
Either approach is socially acceptable. If you're unsure, the tip calculator lets you enter either the subtotal or the post-tax total and calculates from whichever you provide.
How tip percentages have shifted over time
The commonly cited 15% restaurant tip standard is now largely outdated for sit-down dining. The practical baseline has shifted to 18–20% over the past decade, driven by higher urban costs of living, greater public awareness of server wages, and the influence of digital payment systems that default to 20% or higher as the lowest suggested option.
That said, 15% remains entirely appropriate for counter service, takeout, or situations where table service was minimal. Context matters: a 15% tip at a full-service dinner is read differently than a 15% tip for a coffee handed over the counter. The US tipping guide breaks down appropriate ranges for 25+ different service types.
Calculating tips on large or discounted bills
Two scenarios trip people up regularly. The first is a large group bill where the restaurant has already added a service charge. Check your receipt carefully — if 18–20% gratuity is listed as a line item, adding a second tip on top is optional and usually at your discretion based on service quality. Most restaurants add automatic gratuity for parties of six or more.
The second is a discounted or promotional bill. If you have a Groupon, a restaurant week deal, or any other promotional discount, the general rule is to tip on the original pre-discount price, not the promotional total. The server provided full service regardless of the deal you got. On a $90 meal bought at $45 on a promotion, tip on $90. The same principle applies to food delivery tips — tip on the original food price, not the discounted checkout total.
When a tip is optional vs. expected
A useful heuristic: if someone came to your table (or your location) and provided ongoing service — refilling drinks, taking multiple orders, checking in — tipping 18–20% is expected. If you walked up to a counter, placed an order, and picked it up yourself, tipping is optional.
The rise of tablet payment systems has placed tip prompts in contexts where they were historically uncommon — bakeries, coffee shops, fast-casual restaurants, self-checkout. You are not obligated to tip in these situations. A 0% selection is socially acceptable at a counter-service coffee shop even if the screen defaults to 20% as the minimum option. For a detailed breakdown by situation, see the full tipping guide.
Splitting a bill with tip
The cleanest method: calculate the full total including tip first, then divide by the number of people. On a $96 bill at 20%: tip = $19.20, total = $115.20. Split four ways: $115.20 ÷ 4 = $28.80 each.
If different people ordered very different amounts, split the pre-tip bill proportionally first, then calculate each person's tip on their share. The tip calculator has a built-in bill splitter that does this automatically.
A common mistake is to divide the pre-tip bill, then each person adds their own tip separately — this can result in uneven tip totals and confusion for the server. Settling the full tipped amount and splitting that is cleaner.
Frequently asked questions
Tip = Bill Amount × (Tip Percentage ÷ 100). For a $65 bill at 20%: $65 × 0.20 = $13.00 tip. Total = $65 + $13 = $78. To skip the division, move the decimal one place left to find 10%, then double it for 20%.
Move the decimal one place left to get 10% of the bill, then double it for 20%. On a $47 bill: 10% = $4.70, doubled = $9.40 tip. For 15%: find 10%, halve it ($2.35), then add: $4.70 + $2.35 = $7.05.
Etiquette guides recommend tipping on the pre-tax subtotal, but the difference is small. On a $60 bill with 9% tax, a 20% pre-tax tip is $12.00 vs. $13.08 on the post-tax total. Either is acceptable — most people tip on whatever number they see first on the receipt.
Find 10% by moving the decimal left one place, then take half of that for 5%, and add the two together. On a $54 bill: 10% = $5.40, half = $2.70, 15% tip = $5.40 + $2.70 = $8.10.
A 20% tip on $50 is $10.00. Formula: $50 × 0.20 = $10. Total including tip = $60. Quick mental check: move the decimal to get $5 (10%), then double to $10 (20%).
Calculate the full total including tip first, then divide by the number of diners. On a $120 bill with a $24 tip (20%), the total is $144. Split between 4 people: $144 ÷ 4 = $36 each. The tip calculator has a built-in bill splitter.
18–20% is the current standard for sit-down restaurant service. 15% is technically acceptable but increasingly read as below-average by servers. For excellent service, 25% or more. Counter service and takeout: 0–10% is optional, not expected.
Most restaurants automatically add 18–20% gratuity to parties of 6 or more — check your receipt before adding more. If gratuity is not included, the same 18–20% standard applies. On a $300 group bill, a 20% tip is $60, making the total $360.
Leaving no tip is considered very rude in the US, as servers rely on tips for a significant share of their income. For genuinely poor service, 10% signals dissatisfaction while still leaving something. If the issue was kitchen delays or factors outside the server's control, the server generally should not be penalised.