How do I calculate a 20% tip quickly in my head?

Move the decimal point one place left to get 10%, then double it. Example: $47.50 bill → 10% is $4.75 → 20% is $9.50. For 15%, calculate 10% and add half of that amount.

Should I tip on the pre-tax or post-tax amount?

Traditionally, tips are calculated on the pre-tax subtotal. However, tipping on the total including tax is common and acceptable. The difference is usually small (a few cents to a dollar).

Tip Calculator - Calculate Tips and Split Bills

How to Calculate a Tip

The tip formula is straightforward:

Tip Amount = Bill × (Tip Percentage ÷ 100)

Example: Your restaurant bill is $67.50 and you want to leave an 18% tip.

Tip = $67.50 × 0.18 = $12.15
Total = $67.50 + $12.15 = $79.65

Quick Mental Math Tricks

For 20%: Find 10% (move decimal one place left), then double it.

Bill: $45.00 → 10% = $4.50 → 20% = $9.00

For 15%: Find 10%, then add half of that.

Bill: $45.00 → 10% = $4.50 → half of 10% = $2.25 → 15% = $6.75

For 18%: Calculate 20% and subtract a small amount, or calculate 15% and add a bit.

Standard Tipping Guidelines (US)

Service	Typical Tip
Restaurant (sit-down)	15-20%
Buffet	10-15%
Takeout	0-10%
Food Delivery	15-20%
Bartender	$1-2 per drink or 15-20%
Hair Salon/Barber	15-20%
Taxi/Rideshare	15-20%
Hotel Housekeeping	$2-5 per night
Valet Parking	$2-5

Tipping Etiquette Tips

Check for included gratuity: Many restaurants add 18-20% for large parties (6+ people)
Tip on pre-tax amount: It's customary to tip on the subtotal before tax
Cash is appreciated: Servers often prefer cash tips as they receive them immediately
Poor service: Consider speaking with management rather than leaving no tip
International travel: Research local customs - tipping varies greatly by country

Splitting Bills Fairly

When dining with a group, there are several approaches:

Even split: Divide total (with tip) equally among all diners
Itemized: Each person pays for what they ordered plus proportional tip
Venmo/payment apps: One person pays, others reimburse via app

Frequently Asked Questions

How much should I tip at a restaurant?

In the US, 15-20% of the pre-tax bill is standard for good service. 15% for adequate service, 18% for good service, and 20%+ for exceptional service.

Do I tip on the total bill including tax?

Traditionally, tips are calculated on the pre-tax amount. However, many people tip on the total bill for convenience. Either is acceptable.

How do I split a bill with friends?

Use our calculator: enter the bill amount, select tip percentage, and specify the number of people. It automatically calculates each person's share including tip.

Should I tip for takeout orders?

Tipping for takeout is optional but appreciated (10% is common). During busy periods or for large/complex orders, a tip is a nice gesture.

What if service was terrible?

Even with poor service, a 10% tip is often still given. Consider speaking with management about specific issues rather than leaving nothing.

Is tipping different in other countries?

Yes! In many countries (Japan, Korea, parts of Europe), tipping is not expected or can even be considered rude. Always research local customs when traveling.