A price increase percentage tells you how large a price rise is compared with the old price. It can describe rent, groceries, subscriptions, services, or business costs.
Compare an old price with a new price
Price increase % = ((New price − Old price) ÷ Old price) × 100A monthly service changes from $24 to $27.
- Difference: $27 − $24 = $3
- Relative increase: $3 ÷ $24 = 0.125
- Percentage increase: 0.125 × 100 = 12.5%
The service costs $3 more each month, which is a 12.5% increase from the original price.
Add a planned increase to a price
To raise a $45 price by 18%, convert 18% to 0.18 and multiply:
Increase amount = $45 × 0.18 = $8.10
New price = $45 + $8.10 = $53.10You can also multiply $45 by 1.18 in one step.
Price increase is not always markup
A price increase compares a new selling price with an earlier price. Markup usually compares a selling price with cost. Margin uses revenue as its denominator. Those terms may produce different percentages from the same dollar figures.
Taxes and fees can also affect the final amount a customer pays. State and local sales-tax rules vary, so this general arithmetic does not determine a tax obligation.
Avoid dividing by the new price
In the $24 to $27 example, dividing $3 by $27 gives 11.11%. That measures the difference as a share of the new price, not the increase from the old price.
Read why the starting value matters or learn how multiple increases compound.
The short answer
Subtract the old price from the new one, then divide by the old price. Keep the dollar difference beside the percentage so the size of the change remains clear.