How to Calculate Tips in Your Head: 10%, 15%, and 20% Math Tricks
Master easy mental math tricks to calculate 10%, 15%, 18%, and 20% tips instantly without pulling out your smartphone calculator.
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When the waiter drops the check at your table, you don't always want to pull out your phone to calculate the gratuity. Here are simple mental math shortcuts.
The Golden Rule: The 10% Anchor
To find 10% of any bill, simply move the decimal point one place to the left: - Bill is $46.00 ➔ 10% is $4.60 - Bill is $82.50 ➔ 10% is $8.25
How to Calculate 20% (Double the 10%)
Take your 10% anchor and double it: - On a $65 bill, 10% is $6.50. Double that is $13.00 tip.
How to Calculate 15% (10% + Half of 10%)
Take your 10% anchor, divide it in half (to get 5%), and add them together: - On a $40 bill: 10% is $4.00, half is $2.00. Total 15% tip is $6.00.
How to Calculate 18%
Calculate 20% and subtract a dollar or two, or use Toolstack's free online Tip Calculator for exact splits.
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