Methodology

Last updated Oct 12, 2026

Document tools: how totals are calculated

The invoice, estimate and receipt generators run in your browser. They follow these rules:

• Line amount = quantity × unit price, rounded to the cent.
• Subtotal = the sum of all line amounts.
• Discount (a percentage or a fixed amount) is applied to the subtotal before tax. It cannot be larger than the subtotal.
• Tax is calculated once per document, on the lines marked taxable, after their share of the discount.
• Shipping is added after tax and is not taxed.
• Balance due = total minus any amount already paid.

Money is calculated in whole cents to avoid floating-point errors. Amounts are rounded half up (for example, $0.005 becomes $0.01).

The tools do not look up tax rates for you. Enter the rate that applies to your sale; if you are not sure, check with your state revenue agency or a tax professional.

In downloaded PDFs, amounts in euros are shown with the code “EUR” instead of the € symbol, so they print cleanly with standard fonts.

Fees and official data

Pages about state fees and business formation, when published, will use these rules:

• Every fee and rate is taken from an official source, such as a state Secretary of State, a state revenue agency or the IRS.
• Each value is stored with its source link and the date it was checked.
• Fees are re-checked at least every 180 days, and other sources at least every 365 days. A page whose data has not been re-checked in time is not published until it is.

Government fees and rules change. Always confirm the current amount with the agency before you file.

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