Percentage Calculator

About Percentage Calculator

This percentage calculator solves the four most common percent problems side by side. Find a percentage of a number (what is 20% of 150), work out what percent one number is of another, calculate the percentage increase or decrease between two values, and get the sale price and amount saved after a percentage discount. Each card updates as you type and has preset buttons for common values like 10%, 25%, and 50%. Results are rounded to at most four decimal places. Useful for shopping discounts, grades, sales figures, and price changes.

How to use

1. Pick the card that matches your question: Percentage Value, Percentage Ratio, Percentage Change, or Discount & Final Price.
2. Type the two numbers into that card's fields, such as Percentage (%) and Total Value.
3. Tap a preset chip like 20%, 50% Part, +10%, or 30% OFF to fill a field instantly.
4. Read the answer in the card's result box; it updates as you type, Discount also shows the amount saved, and Copy puts the result on your clipboard.

Limitations & notes

• Results are rounded to at most 4 decimal places.
• Percentage Ratio shows a hint instead of a result when the total is 0, and Percentage Change does the same when the starting value is 0.
• Percentage Change divides by the starting value as entered, so with a negative starting value the sign may not match the direction of change.
• The discounted price never goes below 0, so discounts over 100% show a final price of 0.

FAQ

How do I calculate a percentage of a number?

Divide the percentage by 100 and multiply by the number. For example, 20% of 150 is 0.20 × 150 = 30.

How do I find what percent one number is of another?

Divide the part by the total and multiply by 100. For example, 45 out of 60 is 45 / 60 × 100 = 75%.

How do I calculate percentage increase or decrease?

Subtract the old value from the new value, divide by the old value, and multiply by 100. Going from 80 to 100 is a 25% increase, while going from 100 to 80 is a 20% decrease, shown as a negative number.

How do I calculate a discounted price?

Multiply the original price by the discount percentage divided by 100 to get the savings, then subtract that from the price. A 30% discount on $80 saves $24, so the final price is $56.