Daily
Percentage Calculator
Three ways to calculate percentages — what percent, percent of a number, and percent change. Instant answers, no signup.
Real-World Percentage Examples
Sales Tax (8.5%)
$85 on $1,000
Multiply purchase by 0.085 to find tax amount.
Standard Tip (20%)
$12 on $60
Multiply bill by 0.20, or move decimal and double.
Discount (25% off)
$37.50 off $150
Multiply original price by 0.25 to find savings.
Grade (87/100)
87%
Divide your score by total possible, multiply by 100.
Pay Raise (5%)
+$2,500/yr
On a $50,000 salary: 50,000 × 0.05 = $2,500 increase.
Calorie Deficit
250 cal/day
A 12.5% deficit on a 2,000 calorie maintenance target.
How to Calculate Percentages in Your Head
The 10% Trick
To find 10% of any number, just move the decimal point one place to the left. 10% of 250 is 25. 10% of 89 is 8.9. Once you have 10%, you can quickly find 5% (half of 10%), 20% (double 10%), 15% (10% + 5%), and 25% (double 10% + 5%).
Tip Calculations Made Simple
For a 20% tip on a $47 bill: 10% of $47 is $4.70. Double it = $9.40. For 15%: 10% + half of 10% = $4.70 + $2.35 = $7.05. For 18%: 10% + 5% + 3% (which is close enough to 20% minus 2%) ≈ $8.46.
Discount Shopping
For 30% off a $80 item: 10% of $80 is $8. Triple it = $24 off. Final price: $80 − $24 = $56. You can always sanity-check: 70% of $80 = $56. ✓
Frequently Asked Questions
What is 20% of 150?
20% of 150 is 30. To calculate: 150 × 0.20 = 30. Or: find 10% (15) and double it (30).
How do I calculate a percentage increase?
Subtract the original value from the new value, divide by the original value, then multiply by 100. Formula: ((New − Old) / Old) × 100. Example: price goes from $80 to $100 → (($100−$80)/$80)×100 = 25% increase.
How is a grade percentage calculated?
Divide your points earned by the total points possible, then multiply by 100. If you scored 42 out of 50 on a test: (42 ÷ 50) × 100 = 84%. Use the "X is what % of Y" calculator above for any grade calculation.