Calculation type: Finding the original value before a percentage increase (removing the tax). The default rate here is only an example — VAT/GST rates vary by country.
Calculator usage: Use the
Original Before Increase Calculator (“What was the Original value before an Increase % resulted in the New value?”). Enter
20 [B] and $
240 [C]. The calculator will find the price before tax.
Watch out: You cannot simply subtract
20% from the total. $
240 − (
20 /
100) × $
240 = $
192 is NOT correct, because the tax was added to the price before tax, not to the total.
Formula explanation:
We want to find the price before tax, when the total of $
240
already contains
20% VAT/GST.
Formula: Price before tax = Total price / (1 + Tax rate / 100)
Price before tax = $
240 / (1 +
20 / 100) = $
240 /
1.2 = $
200
Tax amount = $
240 − $
200 = $
40