Financial

Sales Tax Calculator

Estimate tax amount, before-tax price, and final total.

Inputs

Adjust the assumptions to match your scenario. Results update instantly.

SubtotalPrice before sales tax is added at checkout.Tax rateSales tax rate that applies to the purchase.Tip rateOptional tip percentage applied to the subtotal.

Results

Primary outputs and comparison insights are built from the current inputs.

Tax amount

$7.13

Sales tax added on top of the subtotal.

Tip amount

$0.00

Optional tip calculated from the subtotal.

Grand total

$102.13

Combined checkout total including tax and any tip.

How this calculator works

The Sales Tax Calculator gives you the tax amount, optional tip, and full checkout total so you can budget purchases or invoices more accurately. Enter subtotal, tax rate, and tip rate to estimate tax amount, tip amount, and grand total. The calculator updates instantly and adds a comparison table plus chart so you can test the sensitivity of the result before you use it in a decision.

Quick guide

Jump straight to the section you need, then return to the calculator.

Inputs Outputs Assumptions Tips Formulas Examples Reference table Visual breakdown References

Inputs

Price before sales tax is added at checkout.
Sales tax rate that applies to the purchase.
Optional tip percentage applied to the subtotal.

Outputs

Sales tax added on top of the subtotal.
Optional tip calculated from the subtotal.
Combined checkout total including tax and any tip.

Assumptions

Tax and tip are both modeled as flat percentages of the subtotal.
The calculator does not handle item-level exemptions or tiered rates.

Tips

Use tip only if it applies to your scenario.
For invoices, confirm whether tax is applied before or after discounts.

Formula guide

Use these formulas to audit the output or explain it to someone else.

2 formulas

Tax Amount = Subtotal × Tax Rate

Grand Total = Subtotal + Tax Amount + Tip Amount

Usage examples

Review a ready-made scenario, copy it, then tweak inputs to match your case.

Example

3 inputs3 outputs

Restaurant total

Inputs

Example input Subtotal: $68.00
Example input Tax rate: 8.25%
Example input Tip rate: 18%

Outputs

Example result Tax amount: $5.61
Example result Tip amount: $12.24
Example result Grand total: $85.85

Tip is often applied to the pre-tax subtotal, so keeping it separate from tax avoids double counting.

Total by tax rate

4 of 4 rows

Tax rate	Tax amount	Grand total
5.5%	$5.23	$100.23
7.5%	$7.13	$102.13
9.5%	$9.03	$104.03
11.5%	$10.93	$105.93

Tax rates differ by location and product type, so use the correct local rate when you rely on the result.

Tax impact on total

Highest: 11.5% ($105.93)Lowest: 5.5% ($100.23)

Sort

Tax rateGrand total

Focus point

5.5%

$100.23

Position

#1 of 4

Original order

Share of total

24.31%

Total: $412.30

PositiveNegative

Tax rates differ by location and product type, so use the correct local rate when you rely on the result.

References

Sales tax arithmetic for checkout calculations
Basic invoice total calculations with tax and tip

FAQ

Common questions

What does the Sales Tax Calculator do?

What inputs do I need?

Typical inputs include Price before sales tax is added at checkout., Sales tax rate that applies to the purchase., Optional tip percentage applied to the subtotal..

How are the results calculated?

We follow the formulas and assumptions outlined in the "How this calculator works" section. You will see outputs like Sales tax added on top of the subtotal., Optional tip calculated from the subtotal., Combined checkout total including tax and any tip..