Invoice Calculator

Calculate invoice totals with multiple line items, tax, and discounts. Perfect for freelancers, contractors, and small business owners.

How it works

Line total = quantity × unit price. Subtotal = sum of line totals. Total due = subtotal − discount + tax (subtotal × tax rate) + shipping.

Worked example

12 hours at $85 is $1,020. Apply a 10% discount ($102) and 8.5% sales tax on $918 ($78.03), and the invoice total is $996.03.

Frequently asked questions

Is tax applied before or after a discount?

After. Discounts reduce the taxable base, so the correct order is subtotal, minus discount, then tax on the discounted amount.

What must an invoice include?

A unique invoice number, issue and due dates, your business and tax details, the client's details, itemised lines, tax shown separately and payment instructions.

What payment terms should freelancers use?

Net 14 or Net 15 gets paid faster than Net 30, and a stated late fee of 1.5% per month plus a deposit for new clients materially reduces overdue invoices.