How to Calculate a Tip — Quick & Easy Guide
Calculating a tip at a restaurant doesn't have to be stressful. Whether you prefer doing mental math or using a calculator, there are simple methods that make it quick and painless. This guide covers everything from the fastest mental math tricks to understanding tip etiquette and splitting bills with a group.
The Simple Formula
Tip Amount = Bill Total × (Tip Percentage ÷ 100)
Total to Pay = Bill Total + Tip Amount
So for a $65 bill with an 18% tip: $65 × 0.18 = $11.70 tip. Total = $76.70.
The Fastest Mental Math Method
The easiest trick for calculating a 20% tip in your head is the "divide by 5" method:
- Take the bill total
- Move the decimal one place left (this gives you 10%)
- Double that number (this gives you 20%)
Example: $85 bill → 10% = $8.50 → 20% = $17.00. Done in seconds, no calculator needed.
For 15%, take 10% and add half of that: $85 → $8.50 + $4.25 = $12.75.
Tip Amount Quick Reference Table
| Bill Total | 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 |
| $50 | $7.50 | $9.00 | $10.00 | $12.50 |
| $75 | $11.25 | $13.50 | $15.00 | $18.75 |
| $100 | $15.00 | $18.00 | $20.00 | $25.00 |
| $150 | $22.50 | $27.00 | $30.00 | $37.50 |
| $200 | $30.00 | $36.00 | $40.00 | $50.00 |
How Much Should You Tip?
Tipping norms vary by country and service type. In the United States, here are the general guidelines:
| Service | Standard Tip | Exceptional Service |
|---|---|---|
| Sit-down restaurant | 18–20% | 25%+ |
| Buffet | 10% | 15% |
| Bar / drinks only | $1–2 per drink | 20% |
| Food delivery | 15–20% | 25% |
| Taxi / rideshare | 15–20% | 25% |
| Hair salon | 15–20% | 25% |
| Hotel housekeeping | $3–5/night | $5–10/night |
| Valet parking | $2–5 | $5–10 |
Should You Tip Before or After Tax?
This is a common debate. Technically, the "pre-tax" amount is the cost of the food and service, so tipping on the pre-tax total is considered standard. However, in practice the difference is small — on a $100 bill with 8% tax, tipping 20% on the pre-tax amount ($100) gives a $20 tip, while tipping on the post-tax amount ($108) gives a $21.60 tip. Many people simply tip on the total shown on the bill for simplicity.
Splitting the Bill with a Group
Splitting evenly is simple: add tip to the total, then divide by the number of people. But what if people ordered different amounts? A few approaches:
- Even split: Everyone pays the same — easiest, works well for similar orders
- Pay what you ordered: Each person calculates their own subtotal plus a proportional share of the tip
- One person pays, others Venmo: Popular and avoids complicated math at the table
When a Gratuity Is Already Included
Many restaurants automatically add a gratuity for large groups (usually 6 or more people). Always check your bill for a line item labeled "gratuity," "service charge," or "auto-gratuity" before adding an additional tip. You don't need to tip twice — though leaving a small extra amount for exceptional service is always appreciated.
Let our free tip calculator do the math instantly.
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