Add sales tax or VAT to a price at any rate — works for US states, EU VAT, or anywhere.
Sales tax rates vary by US state/city and VAT varies by EU country, so this calculator lets you enter the exact local rate. A future version can auto-suggest a rate based on detected region (see the site's geo-detection framework).
US sales tax is a single-stage tax — charged only once, at the final sale to the end consumer — which sounds simple, but the actual rate you pay is anything but uniform. Statewide general sales tax rates alone range from 2.90% in Colorado to 7.25% in California, and that's before local layers: in "home rule" states, individual counties and cities can set their own additional sales tax on top of the state rate, which is exactly why the combined rate for the same purchase can differ meaningfully between two towns in the same state. Louisiana's average combined state-and-local rate, for example, runs around 10.11% once local additions are factored in — more than three times Colorado's bare state rate.
The other major complexity is "nexus" — the legal connection that determines whether a seller must collect sales tax in a given state at all. Historically this meant physical presence (a store, warehouse or employee in that state), but since the concept of economic nexus was established, an out-of-state online seller can be required to register and collect sales tax in a state purely by exceeding that state's sales threshold there — commonly $100,000 in annual sales or 200 separate transactions, though exact thresholds, what counts toward them, and whether marketplace sales are included all vary meaningfully by state. This is precisely why the same product bought from the same online retailer can show a different sales tax rate (or none at all) depending on your shipping address — the seller's nexus obligations, combined with your specific state, county and city rates, determine the final number, not a single nationwide rate.
Because sales tax is set at the state level with no federal standard, and rates alone range from 2.90% (Colorado) to 7.25% (California) for the state portion. Local counties and cities in many "home rule" states can add their own additional sales tax on top, pushing combined rates even higher — Louisiana's average combined rate runs around 10.11%.
Nexus is the legal connection that determines whether a seller must collect sales tax in a given state. It used to require physical presence (a store or warehouse), but economic nexus rules now mean an online seller can be required to collect tax in a state purely by exceeding a sales threshold there — commonly $100,000 in annual sales or 200 transactions, though exact rules vary by state.
Because the applicable rate depends on both the seller's nexus obligations (whether they're required to collect tax in your specific state at all) and your exact state, county and city rates combined. There's no single nationwide sales tax rate — the final number is assembled from multiple layers that vary by your specific location and the seller's registration status.
Sales tax is charged only once, at the final sale to the consumer, with no mechanism for businesses to reclaim tax paid on their own purchases (a reseller typically avoids paying it upfront using a resale certificate instead). VAT, by contrast, is charged at every stage of the supply chain, with businesses reclaiming what they paid via input tax credits — a structurally different system covered on our dedicated VAT calculator.