This calculator follows a common invoice order: subtract the discount from the subtotal, calculate tax on the discounted amount, then add shipping. Amount paid is subtracted from the final total to produce the balance due.
Tax bases and discount rules vary, especially for shipping or mixed taxable items. Use the result as a check, then apply the rules that govern the actual transaction in your accounting system or invoice.
Invoice total formula
Discount = subtotal × discount rate. Taxable amount = subtotal − discount. Tax = taxable amount × tax rate. Total = taxable amount + tax + shipping. Balance due = total − amount paid.
If a fixed discount or tax applies only to selected lines, calculate those lines separately. The full invoice generator supports itemized rates and produces the final document.
Turn the result into a real document
The calculator is for the math. Use the free generator to itemize the work, add customer details and download a PDF, Word or Excel file.
Create an invoiceContinue through the invoice workflow
Frequently asked questions
Is tax calculated before or after a discount?
This calculator applies tax after the discount, a common method. Local rules and the type of discount can change the required tax base.
How is balance due calculated?
Balance due is the invoice total minus payments already received.
Can I turn the calculation into an invoice?
Yes. Open the invoice generator and add the subtotal as itemized line items, then set the same discount, tax, shipping and payment.