How to Calculate a Tip and Split It
Calculating a tip and splitting it among friends is straightforward once you know the formula. The standard approach is: multiply your bill subtotal by the tip percentage to get the tip amount, add the tip to the total bill (including tax), then divide by the number of people. Here is the step-by-step formula:
- Find the tip amount: Bill subtotal × tip percentage = tip. For example, $100 × 0.20 = $20 tip.
- Calculate the grand total: Bill subtotal + tax + tip = grand total. So $100 + $8.50 tax + $20 tip = $128.50.
- Divide by people: Grand total ÷ number of people = each person's share. $128.50 ÷ 4 = $32.13 per person.
That's the core math. But real-world tip splitting involves more nuance — should you tip on the pre-tax or post-tax amount? What if people ordered wildly different things? What about different service types? This guide covers all of it.
Standard Tipping Percentages by Service Type
Tipping norms vary by industry. While there are no hard rules, these are the widely accepted percentages across the United States. Using the right percentage for each service type ensures you're tipping fairly without under- or over-paying.
| Service Type | Typical Range | Notes |
|---|---|---|
| Sit-down restaurant | 15–25% | 20% is standard for good service; 25% for exceptional |
| Food delivery | 15–20% | Minimum $3–5; tip more in bad weather or for large orders |
| Coffee / takeout | $1–2 or 10–15% | Not required but increasingly expected, especially at cafes |
| Hair salon / barber | 15–25% | 20% is standard; tip more for color or complex styling |
| Taxi / rideshare | 15–20% | Tip in-app for rideshares; cash tips appreciated by taxi drivers |
| Bartender | $1–2 per drink or 15–20% | Per-drink tipping for simple orders; percentage for tabs |
| Hotel housekeeping | $2–5 per night | Leave daily rather than at checkout (different staff may clean) |
| Spa / massage | 15–25% | Check if gratuity is already included in the service price |
Should You Tip on the Pre-Tax or Post-Tax Amount?
This is one of the most debated questions in tipping etiquette, and there's no single right answer. Traditionally, etiquette experts like the Emily Post Institute recommend tipping on the pre-tax subtotal. The logic is simple: the tip is for the server's service, and sales tax is a government charge that has nothing to do with the quality of service you received.
In practice, the difference is small. On a $100 bill with 8.5% tax, a 20% tip on the pre-tax amount is $20.00, while a 20% tip on the post-tax amount ($108.50) is $21.70. That's only $1.70 more. Most people today tip on the post-tax total because that's the number they see on the receipt, and few bother to subtract the tax first.
Our tip split calculator lets you choose either approach. If you want to tip on the pre-tax amount, enter just the food subtotal as your bill amount and add the tax separately. The calculator will compute the tip on the subtotal and add tax on top, giving you the most accurate per-person breakdown.
Real-World Example: $150 Dinner Bill, 4 People, 20% Tip
Let's walk through a realistic dinner scenario step by step. You go out with three friends to a restaurant. The food subtotal comes to $150.00, and your local sales tax rate is 8.5%.
- Bill subtotal: $150.00
- Tax (8.5%): $150.00 × 0.085 = $12.75
- Tip (20% on pre-tax): $150.00 × 0.20 = $30.00
- Grand total: $150.00 + $12.75 + $30.00 = $192.75
- Per person (4 people): $192.75 ÷ 4 = $48.19 each
Without a calculator, most people would round up to $50 each, leaving $200 on the table — that's $7.25 overpaid collectively. Our calculator gives you the exact amount so nobody overpays and the server still gets a proper tip.
How to Split a Tip When People Ordered Different Amounts
Equal tip splitting feels unfair when one person ordered a $15 salad and another had a $60 steak with cocktails. In these situations, the fairest method is to split the tip proportionally based on what each person ordered.
Here's how proportional tip splitting works: each person calculates the tip on their own items, then adds their share of tax. For example, on a $200 bill with four diners:
- Person A: Ordered $80 worth of food → 40% of the bill → pays 40% of the tip ($8 on a $20 tip) → total share: $80 + $6.80 tax + $8 tip = $94.80
- Person B: Ordered $50 worth → 25% → pays 25% of the tip ($5) → total share: $50 + $4.25 tax + $5 tip = $59.25
- Person C: Ordered $40 worth → 20% → pays 20% of the tip ($4) → total share: $40 + $3.40 tax + $4 tip = $47.40
- Person D: Ordered $30 worth → 15% → pays 15% of the tip ($3) → total share: $30 + $2.55 tax + $3 tip = $35.55
This approach respects the fact that the person who ordered more should contribute more to the tip, since the server's workload often correlates with the order size. Our bill split calculator handles this per-item splitting automatically — just assign items to each person and the math is done for you.
Tip Calculator vs. Google's Built-In Tip Calculator
If you search “tip calculator” on Google, you'll see a simple built-in widget that lets you enter a bill amount, choose a tip percentage, and see the total. It works fine for solo diners, but it has a major limitation: Google's tip calculator doesn't split between people. There's no option to divide the tip or total among a group, which is the exact scenario most people need help with.
SplitGenius's tip split calculator is built specifically for groups. You enter the bill amount, tip percentage, number of people, and optionally the tax — and it instantly shows each person's total, broken down into their share of the food, tax, and tip. You can also generate a shareable link so everyone in the group sees the same breakdown on their own phone, eliminating the back-and-forth of “how much do I owe?”
Other differences: SplitGenius handles tax separately (Google lumps everything together), lets you round up or down to clean dollar amounts, and works entirely in your browser with no app download or account required.
Quick Tips for Tipping Like a Pro
- The double-tax shortcut: In many U.S. states, sales tax is around 8–10%. Doubling the tax gives you a quick 16–20% tip estimate without any math.
- Move the decimal: To calculate 10% of any bill, just move the decimal point one place left ($85.00 → $8.50). Double it for 20% ($17.00). Add half for 15% ($12.75).
- Check for auto-gratuity: Many restaurants add 18–20% gratuity automatically for groups of 6 or more. Always check your bill before adding an additional tip on top.
- Tip on discounts generously: If you used a coupon or got a discount, tip on the original pre-discount amount. The server did the same amount of work regardless of your discount.
- Cash tips still matter: Even if you pay by card, leaving a cash tip ensures the server gets the full amount without waiting for payroll processing.
When Is It Okay Not to Tip?
Tipping is deeply embedded in American dining culture, but there are situations where it's genuinely optional or not expected. Counter-service restaurants where you order at a register and pick up your own food traditionally did not expect tips, though digital payment screens have made tip prompts ubiquitous. Fast food, grocery stores, and retail shops do not have a tipping culture. If you're traveling internationally, research local customs — in Japan, tipping is considered rude, while in much of Europe a service charge is included in the price.
For a comprehensive breakdown of when, where, and how much to tip in every situation, check out our complete tipping guide.