Reverse Sales Tax Calculator
Enter a total and a tax rate to get the price before tax — or enter a total and the tax amount from a receipt and it works out the rate you were charged, which none of the other reverse sales tax calculators do. It also builds a combined rate from state, county and city parts, and splits a receipt with several lines.
Build the rate from state, county and city parts
Fill any of these in and they replace the single rate above. The tax is then split back across them so you can see where it went.
Price before tax
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Your receipt shows a total and a tax amount but not the percentage. Put both in and this works out the rate you were charged.
Tax rate charged
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Why there is a range
For a receipt with several lines, or with different rates on different items. Each line can be entered with tax already included or not.
| Description | Amount | Rate % | Tax included? |
|---|
Net total, before tax
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| Line | Net | Tax | Gross |
|---|
This is arithmetic, not tax advice, and it does not know the rules where you are. Which items are taxable, whether tax applies to shipping, and how a jurisdiction rounds are all local questions this cannot answer. Everything is calculated in your browser and nothing is uploaded.
Runs in your browser. Nothing uploaded.
How to use it
- Take tax off a price. Enter the total you paid and the rate. The price before tax is the total divided by one plus the rate.
- Find the rate. If the receipt shows a total and a tax amount but no percentage, use the second tab. It works out the rate — the thing every other reverse sales tax calculator asks you to already know.
- Split a receipt. Several lines, or different rates on different items, reconciled against the receipt total.
Nothing is uploaded, there’s no share link, and there are no ads.
The formulas
| To find | Formula | Example |
|---|---|---|
| Price before tax | gross ÷ (1 + rate) |
108.25 ÷ 1.0825 = 100.00 |
| The tax | gross − net |
108.25 − 100.00 = 8.25 |
| The rate, from a receipt | tax ÷ (gross − tax) |
4.07 ÷ 50.25 = 8.1% |
| A component’s share | tax × (part ÷ combined) |
8.25 × (6.25 ÷ 8.25) = 6.25 |
The mistake almost everyone makes
You cannot take 8.25% off the total to remove 8.25% tax.
Take 8.25% off 108.25 and you get 99.32. The right answer is 100.00. The gap exists because the tax was charged on the pre-tax price, not on the total — so the 8.25% you’re trying to remove was calculated against a smaller number than the one you’re now holding.
It’s a small error on a coffee and a large one on a van.
Finding the rate when the receipt doesn’t show it
This is the case the other calculators don’t cover, and it’s the more common one. Plenty of receipts print a subtotal, a tax amount and a total, and never the percentage.
Subtract the tax from the total to get the pre-tax price, then divide the tax by that:
4.07 ÷ (54.32 − 4.07) = 4.07 ÷ 50.25 = 8.0995%
Which is 8.1%. And that gap — 8.0995% against 8.1% — is worth understanding rather than ignoring.
Why your receipt’s rate looks slightly off
Because tax is rounded to the nearest cent before it’s printed.
A receipt showing 4.07 of tax was really charging somewhere between 4.065 and 4.075 — anything in that range rounds to 4.07. So the receipt doesn’t point at one rate. It points at a band of rates that would all produce identical figures:
| Pre-tax price | Tax shown | Rates that would print it | Most likely |
|---|---|---|---|
| 50.25 | 4.07 | 8.0896% – 8.1095% | 8.1% |
| 100.00 | 7.00 | 6.995% – 7.005% | 7% |
| 1,000.00 | 93.75 | 9.3745% – 9.3755% | 9.375% |
| 12.99 | 0.82 | 6.2741% – 6.3510% | 6.3% or 6.35% |
Look at the last row. On a small receipt the band is wide enough to contain two rates a real jurisdiction might publish, and there is no way to tell which. This tool says so rather than picking one and letting you assume it’s settled. A larger receipt at the same rate narrows the band until only one answer fits.
How it picks the likely rate
Not by rounding to two decimal places — that would report 8.24% where the answer is 8.25%, because both have two decimals and 8.24 comes first.
Instead it prefers round numbers over short ones. Whole percentages first, then halves, then quarters, then eighths, then tenths. That’s where published rates actually sit: 8.25% is a quarter, 9.375% is an eighth, 6.35% is a twentieth. A rate of 8.24% is arithmetically possible and no tax authority has ever published one.
Combining state, county and city rates
US sales tax is stacked. A single “8.25%” is usually several separate levies added together, and the combined figure is the number people don’t have.
Add the components and use the total. Then, because each part is charged on the same taxable amount, the tax splits back across them in proportion:
| Level | Rate | Share of 8.25 tax |
|---|---|---|
| State | 6.25% | 6.25 |
| County | 1.00% | 1.00 |
| City | 1.00% | 1.00 |
| Combined | 8.25% | 8.25 |
That apportionment is exact whenever every level taxes the same base, which is the normal arrangement. Where a special district taxes only certain goods it becomes an approximation, and you’d need the jurisdiction’s own rules to do better.
A worked example, start to finish
A receipt reads: total 54.32, tax 4.07. No rate printed.
| Step | Working | Result |
|---|---|---|
| Pre-tax price | 54.32 − 4.07 | 50.25 |
| Rate, exactly | 4.07 ÷ 50.25 | 8.0995% |
| Rounding band | 4.065 ÷ 50.25 to 4.075 ÷ 50.25 | 8.0896% – 8.1095% |
| Likely rate | the roundest value in that band | 8.1% |
| Check | 50.25 × 8.1% | 4.07 ✓ |
The last line is the one that matters. Feed 8.1% back in and it reproduces the receipt exactly, which is what makes the answer trustworthy rather than merely plausible.
Sales tax and VAT are the same arithmetic, different rules
Removing VAT from a gross price is the identical calculation — 120 at 20% VAT comes from a net of 100. The tool handles it; pick the currency and enter the rate.
What differs is everything around the maths. VAT is normally shown inside the advertised price, US sales tax is normally added at the till. Zero-rating and exemptions differ wildly by country and by product. And whether tax applies to shipping is a local question with no general answer.
Common problems
| Symptom | What’s happening | Fix |
|---|---|---|
| The answer is a few cents off the receipt | The retailer rounded tax per line; you calculated it on the total | Use the split tab, one line per item |
| The rate comes out as 8.0995% | Normal — the tax was rounded to the cent | Read the likely rate, not the exact one |
| Two rates are offered | The receipt is too small to distinguish them | Use a larger receipt at the same rate |
| “Tax is larger than the total” | The two figures are the wrong way round | The total is the bigger number, tax included |
| Lines don’t sum to the receipt total | A missing line, a wrong rate, or per-line rounding | The tool names the size of the gap |
| A rate over 100% is flagged | The tax amount was typed into the rate box | The rate is a percentage, not money |
What this doesn’t know
It doesn’t know the rate where you are, and that’s deliberate. Rates change several times a year across thousands of local jurisdictions. A built-in table would be wrong somewhere within months, and a wrong rate in a money tool is worse than no rate because it gets believed. Your state revenue department publishes the current figure.
It also isn’t tax advice. Which items are taxable, whether shipping is taxed, how your jurisdiction rounds, and what you can reclaim are all local questions this can’t answer. It does arithmetic, shows its working, and stops there.
Frequently asked questions
How do you calculate reverse sales tax?
Divide the total by one plus the tax rate as a decimal. At 8.25%, a total of 108.25 divided by 1.0825 gives a pre-tax price of 100.00, and the tax is the 8.25 difference. The mistake to avoid is taking 8.25% off the total instead — that gives 99.32, which is wrong, because the tax was charged on the pre-tax price and not on the total.
How do I find the tax rate if my receipt does not show it?
Subtract the tax from the total to get the pre-tax price, then divide the tax by that. A receipt showing 54.32 with 4.07 of tax has a pre-tax price of 50.25, and 4.07 divided by 50.25 is 8.1%. This is the calculation the other reverse sales tax calculators leave out — they all require you to already know the rate, which is exactly the thing a receipt often does not tell you.
Why does the calculated rate come out slightly odd, like 8.0995%?
Because the tax on a receipt is rounded to the nearest cent. That rounding means a receipt does not point at one exact rate, it points at a narrow range of rates that would all print the same figures. This tool shows the range and then names the rate a jurisdiction would actually publish — quarters and eighths, so 8.25% rather than 8.24%. Where more than one plausible rate fits the range, it says so instead of picking one and letting you assume it is proven.
How do I combine state, county and city sales tax?
Add the percentages together and use the total. A 6.25% state rate with a 1% county rate and a 1% city rate is a combined 8.25%. The builder here does that for you and then splits the tax back across the three, so you can see how much of your 8.25 went to each. That apportionment is exact when all three are charged on the same taxable amount, which is the normal arrangement.
Is this the same as a VAT calculator?
The arithmetic is identical — VAT-inclusive prices come apart the same way, and the tool handles them if you pick the right currency and rate. What differs is the rules. VAT is usually shown inclusive on consumer prices, US sales tax is usually added at the till, and which goods are zero-rated or exempt varies enormously. This tool does the maths and makes no claim about the rules where you are.
Can I split a receipt where different items had different rates?
Yes, that is the third tab. Add a line per item or per rate, say whether each amount already includes tax, and it gives you the net, the tax and the gross for each line plus the totals. It also shows the blended rate across the whole receipt, which is not the same as any individual line rate when the rates differ. Enter the receipt total as well and it will tell you if the lines do not add up to it.
The lines do not add up to my receipt total. What went wrong?
Usually one of three things. A line is missing, often a fee or a deposit that is taxed differently. A rate is wrong for one of the items. Or the retailer rounded the tax on each line separately while you calculated it on the total, which can shift the answer by a cent or two on a long receipt. The tool names the size of the gap so you can tell a rounding difference from a real one.
Does this know the sales tax rate where I live?
No, deliberately. Rates change several times a year across thousands of local jurisdictions, and a stale rate in a money tool is worse than no rate because it gets believed. You enter the rate you know, or build it from the parts, and the tool does the arithmetic. Your state revenue department publishes the current rate, and it is worth checking there rather than trusting any calculator including this one.
Is my data sent anywhere?
No. Everything is worked out inside the page by your browser and nothing is transmitted. There is no share link on this tool either, and no ads — which is worth saying because the pages currently ranking for this search carry as many as nine ad units around a calculator with two input boxes.
Guides that use this tool
Last updated: September 1, 2026