How to calculate a 20% tip
A 20% tip equals the tip base multiplied by 0.20. That means a $50 bill produces a $10 tip, an $85 bill produces a $17 tip, and a $120 bill produces a $24 tip.
Twenty percent is also easy to estimate mentally: find 10% of the bill and double it. The calculator above is more useful when you also need tax, service charges, or a precise per-person split.
For U.S. sit-down wait service, the Emily Post Institute currently lists 15% to 20% of the pre-tax bill as a general guideline. Twenty percent is therefore a common comparison point, not a mandatory amount for every transaction.
Quick 20% tip examples
| Bill | 20% tip | Total before tax or fees |
|---|---|---|
| $20 | $4.00 | $24.00 |
| $50 | $10.00 | $60.00 |
| $75 | $15.00 | $90.00 |
| $100 | $20.00 | $120.00 |
| $150 | $30.00 | $180.00 |
Pre-tax versus after-tax 20%
A 20% tip on a pre-tax subtotal is smaller than 20% on the taxed total. If a $100 subtotal has $8 of tax, 20% of the subtotal is $20 while 20% of $108 is $21.60. The Tip Calculator With Tax shows both methods without requiring separate calculations.
Check for service charges first
A required service charge or automatic gratuity is not automatically the same thing as a voluntary tip. If a check already includes a mandatory charge, keep it visible as its own line before deciding whether to add anything extra. The Service Charge vs. Tip guide explains the distinction in more detail.
Split a 20% tip accurately
For an equal group split, use the Split Bill Calculator so every remainder cent is assigned. If different diners ordered different amounts, the Uneven Split Bill Calculator is a better fit.
Compare 20% with nearby amounts
Use the 15% Tip Calculator, 18% Tip Calculator, or 25% Tip Calculator when you want to compare the dollar difference before choosing a voluntary tip.