About the Flexport tariff simulator

Flexport’s US Tariff & Import Duty Calculator is a free app that lets you see exactly what U.S. Customs will charge for any commodity—under every relevant scenario and parameter—in seconds. Type or paste your 10-digit HTS (HS) code, pick an origin country, and the tool instantly returns:

• The legally binding duty rate and any Section 301/232 surcharges—fully aligned with the latest Trump-era lists and subsequent modifications.
• A side-by-side rate comparison for alternative sourcing countries, so you can model “what-if” moves out of China or into Mexico/Vietnam.
• Flags for preferential trade programmes (USMCA, GSP, AGOA, etc.) that could take your duty to 0 %.
• A plain-English breakdown of how the charge is calculated, including ad-valorem, specific, and combination rates.
• Automatic adjustment for the entry date and date of loading, ensuring the duty rate shown is the one that will actually apply on the day your goods clear customs.
• Precise Section 232 calculations that factor in the declared percentage of steel or aluminium content for products subject to metal duties.
• Instant surfacing of special programme indicators (SPI)—e.g. code “A” for GSP or “MX” for USMCA—so you never miss an eligibility-driven reduction.