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Business calculators, then the invoice.

Quick answers to the numbers behind your documents: what to charge, how much tax to add, when an invoice is due and what to bill when it is late. Each calculator explains its formula and sends the result straight to a free invoice or quote generator.

Late Fee CalculatorDays late, flat fee and simple interest on an overdue invoice.Open the calculator →Sales Tax & VAT CalculatorAdd or extract sales tax, VAT or GST at any rate.Open the calculator →Markup & Margin CalculatorCost, price, markup and margin: enter two, get the rest.Open the calculator →Invoice Due Date CalculatorDue date from payment terms, with 2/10 Net 30 discounts.Open the calculator →Freelance Hourly Rate CalculatorHourly rate from target income, costs and billable hours.Open the calculator →

Which calculator do I need?

Setting a price
Start with the hourly rate calculator if you sell your time, or the markup and margin calculator if you resell products. A 50% markup is only a 33% margin, a common pricing mistake.
Adding tax
The sales tax and VAT calculator adds tax to a net price or takes it out of a price that already includes it, with EU, UK, Canadian, Australian and Indian rates.
Getting paid on time
The invoice due date calculator turns terms such as Net 30 or 2/10 Net 30 into a calendar date. If the date has passed, the late fee calculator works out the fee or interest, as long as your contract or invoice terms allow one.

The calculators run in your browser and nothing you type is stored. Results are general information, not tax, legal or accounting advice. New to a term? Read the business document glossary.