Reverse Percentage Calculator

Work backward from a final number to find the original value before an increase, decrease, discount, tax, VAT, or percentage relationship.

Formula

Reverse percentages use the final value and percentage relationship to recover the starting value.

original after increase = final ÷ (1 + percent/100) original after decrease = final ÷ (1 - percent/100) whole when part is p% = part ÷ (p/100)

Short, practical answers for this calculation.

Use it when you know the final value and the percentage relationship but need the original value.

Divide the sale price by 1 minus the discount rate. For 20% off, divide by 0.80.

Divide the gross price by 1 plus the VAT or tax rate.

Because the percentage is based on the original value, not the final value.

Keep the topic tight: discounts, tax, VAT, markup, tips, grades, and percentage change.

All-in-one calculator for percent of a number, percent change, reverse percentages, increases, decreases, and conversions.

Calculate percentage increase or decrease from an old value to a new value.

Calculate sale price, savings, and original price from discount percentages.

Add or remove sales tax and estimate before-tax and after-tax prices.

Add or remove VAT and calculate net price, gross price, and VAT amount.

Calculate markup percentage, selling price, cost, and gross profit.

Calculate profit margin, markup, revenue, cost, and profit.

Calculate tips, totals, and split bills quickly.

Convert test scores into percentages and letter-grade style ranges.