How to use it
Type the starting number and the percent. Choose Increase to add the percent, or Decrease to take it off. You get the new number and the amount that changed.
The formula
- Increase: new = start × (1 + percent ÷ 100)
- Decrease: new = start × (1 − percent ÷ 100)
Example: an ₱25,000 salary with an 8% raise is 25,000 × 1.08 = ₱27,000. The raise itself is ₱2,000.
Common questions
If a price goes up 10% and then down 10%, is it back where it started?
No. ₱100 up 10% is ₱110. Then 10% off ₱110 is ₱11, so it lands at ₱99. The second percent is taken from a bigger number, so it takes off more.
How do I add VAT to a price?
In the Philippines, VAT is 12%. Put the price before VAT here and choose Increase with 12. ₱1,000 becomes ₱1,120.
How do I find the percent between two numbers I already know?
Use the percentage change calculator. It works out the percent from an old number and a new one.
Last checked: 2026-09-25