Sales Tax Guides

Practical guides on how sales tax works, how to calculate it forwards and backwards, and when local rates change the answer.

formulabasics

How Reverse Sales Tax Works

A practical guide to working backwards from a tax-included total to find the original pre-tax price.

how-toformula

Step-by-step instructions for removing sales tax from a final total, plus common mistakes to avoid.

referencerates

A reference guide to state sales tax rates, average local add-ons, and combined rates for supported locations.

formulamath

A focused breakdown of the reverse tax formula, with examples and edge cases.

VATinternational

A clear explanation of how VAT and US sales tax differ and why the reverse calculation still works similarly.

consumerbasics

A consumer-friendly explanation of why shelf prices and receipt totals often do not match.

The guides explain the reasoning, but if you just need an answer right now, jump straight into one of the tools below.