Calculating your pre-tax price is straightforward once you know the Reverse Sales Tax formula and what each input means. This guide explains the method in plain language, walks through a manual calculation, and gives worked examples you can follow — then you can do it instantly with the Reverse Sales Tax Calculator.
What is Reverse Sales Tax?
The Reverse Sales Tax calculation tells you your pre-tax price from a few simple inputs. The figure you are solving for here is the pre-tax price, expressed in INR.
The Reverse Sales Tax formula
The core formula is:
Pre-tax price = Total price (tax included) ÷ (1 + Tax rate ÷ 100)Here is what each input means:
- Total price (tax included) — a money amount. Example: ₹1,180.
- Tax rate — a percentage, such as an annual rate. Example: 18%.
How to calculate it step by step
- Write down the total price (tax included) (for example, ₹1,180).
- Write down the tax rate (for example, 18%).
- Apply the formula above to get your pre-tax price.
- Double-check the result with the Reverse Sales Tax Calculator.
Worked examples
Example 1
| Input / Output | Value |
|---|---|
| Total price (tax included) | ₹1,180 |
| Tax rate | 18% |
| Pre-tax price | ₹1,000.00 |
| Tax amount | ₹180.00 |
With total price (tax included) of ₹1,180 and tax rate of 18%, the pre-tax price works out to ₹1,000.00.
Example 2
With total price (tax included) of ₹2,400 and tax rate of 18%, the pre-tax price works out to ₹2,033.90.
| Result | Value |
|---|---|
| Pre-tax price | ₹2,033.90 |
| Tax amount | ₹366.10 |
Example 3
With total price (tax included) of ₹590 and tax rate of 18%, the pre-tax price works out to ₹500.00.
| Result | Value |
|---|---|
| Pre-tax price | ₹500.00 |
| Tax amount | ₹90.00 |
Tips for an accurate result
- Keep your units consistent — mixing, say, months with years or grams with kilograms is the most common source of error.
- Round only at the very end. Rounding inputs early can shift the final answer noticeably.
- Re-run the numbers whenever an input changes, rather than estimating from an old result.
- Annual rates must be converted to the period you are calculating for (for example, divide an annual rate by 12 for a monthly figure).
Prefer not to do the maths by hand? — the Reverse Sales Tax Calculator does it instantly, for free, with the formula and a worked example built in.
Related calculators
Continue exploring tax calculators with these tools: GST Calculator, Income Tax Calculator, HRA Calculator, Take-Home Salary Calculator, Old vs New Tax Regime Calculator.