Frequently Asked Questions
What is an HS code?
A standardized 6-to-10-digit number that classifies a traded product. Customs authorities use it worldwide to apply the correct tariff rate and collect trade statistics.
How do I find the right HS code for my product?
Browse ExportSonar by chapter to narrow down the section your product belongs to, then pick the 4-digit heading that best matches its material and function. For legal certainty, confirm the final classification with your customs broker.
Is the ExportSonar tariff calculator free?
Yes — looking up US tariff rates and estimating duties is completely free, with no account required.
Do tariff rates differ by country of origin?
Yes. The US applies different general and special rates depending on the country of origin, and free-trade agreements or trade remedies can change the payable rate significantly.
What is the difference between ad valorem and specific duties?
Ad valorem duty is a percentage of the shipment value. Specific duty is a fixed amount per unit of quantity, such as dollars per kilogram. Many HTS lines combine both.
How current are the rates shown?
Rates are imported from the official US Harmonized Tariff Schedule and refreshed regularly. Always verify the final rate with US Customs before entry.