USTariffRates

Best import duty calculator

Best Import Duty Calculators for US Importers

Compare the best import duty calculators for HTS lookup, US customs duty estimates, tariff overlays, and landed-cost planning.

Checked Published by US Tariff Rates, one of the products compared
Calculate US import dutyAPI options

How this comparison was made

This page compares import duty calculators on what each one publicly documents: the duty layers it shows, its price, free access and API. A broker needs an auditable HTS and duty stack, a sourcing team needs country scenarios, and an ecommerce team needs an estimate before repricing; the table shows which options document each.

  • Every statement about another product restates that product's own public page as read on October 8, 2026, and links it. Where a vendor does not publish a fact, the table says so.
  • Statements about US Tariff Rates come from its published plans and API documentation, linked the same way.
  • Limits: we did not buy or test the paid tiers of other products; prices and features change after the check date; we publish US Tariff Rates, so weigh our own row accordingly.

What each option is compared on

Uses HTS-level duty data instead of only broad HS6 categories.
Shows surcharge layers such as Section 301, Section 232, and trade-remedy risk.
Separates duty from customs fees, freight, and insurance inputs.
Links back to official tariff or ruling sources when the decision needs review.

Side-by-side facts

As published by each product on October 8, 2026. Each cell links the page it was read from.

ProductPublished priceFree accessAPIUS duty layers statedCoverage
US Tariff Rates

US import tariff lookup, landed-cost calculator and REST API for HTS codes. Each duty program is returned as its own layer rather than one combined rate.

Free $0.00; Pro $49.00 a month or $399.00 a year; Team $199.00 a month or $1,590.00 a year; Enterprise quoted. sourceFree plan: 50 API requests a month, 10 rows per bulk lookup, 5 watchlist alerts. sourcePublic REST documentation and an OpenAPI 3.1 file. Hosted MCP server at mcp.ustariffrates.com, authenticated with the same API key. sourceLookup responses return a rate_stack of per-program duty layers (for example, base_mfn, section_122, section_232 and section_301), plus total_additional_pct and total_estimated. sourceUS imports only (US HTS). source
Flexport Tariff Simulator

Web tool estimating US import duties from shipment value, origin and HTS code.

Free; a Pro tier requires a Flexport account, no separate price stated. sourceUp to 10 HTS codes without an account. sourceNo simulator API stated. sourceStates results are broken down by tariff type; programs not named. sourceUS import duties by country of origin; states it includes every current US HTS code. source
USITC HTS search and HTS REST API

The official online Harmonized Tariff Schedule, maintained by the USITC Office of Tariff Affairs and Trade Agreements.

No fee stated; search and API answered without login or key. sourcePublic, no account. sourceREST API at hts.usitc.gov/reststop answered without a key: /search returns JSON; /exportList returns JSON or CSV. sourcePublishes Chapter 99 headings (for example 9903.88.15) as separate HTS entries; does not compute a combined duty for a product. sourceUS only. source

Options by job

US Tariff Rates landed cost calculator

Use when: You need an HTS search and an itemized US duty stack in one step.

Open calculator

Documented

  • HTS search by product description or code in the same form as the calculation.
  • Itemizes base duty, Section 301, Section 232, Section 122, MPF, HMF, freight and insurance.
  • The same lookup is available through the watchlist and the API.

Limits

  • Final customs classification still needs professional review for complex goods.
  • Not a binding classification ruling; only CBP issues those.
  • AD/CVD results (risk_layers) are screening context with the underlying orders, not entry liability. source

Flexport Tariff Simulator

Use when: You want a free US duty estimate for a few HTS codes without an account.

Open source

Documented

  • Free for up to 10 HTS codes without an account.
  • Results broken down by tariff type.

Limits

  • No simulator API stated.
  • States the simulator is updated within 48 hours of an official tariff change. source
  • Bulk upload, fees, comparisons and alerts require Pro. source

USITC HTS search

Use when: You need the official tariff schedule text.

Open source

Documented

  • Official US Harmonized Tariff Schedule, with Chapter 99 headings as separate entries.
  • Documented REST API for search and export.

Limits

  • Not a landed-cost calculator.
  • The user combines base duty and Chapter 99 programs.
  • The search site renders in the browser with JavaScript. source

Spreadsheet landed-cost model

Use when: Your team has custom internal costing assumptions.

Documented

  • Holds internal freight, insurance, margin, and warehouse cost assumptions.
  • Adapts to product-specific pricing reviews.

Limits

  • Tariff data goes stale unless connected to a current HTS source.
  • Harder to audit when duty formulas and assumptions spread across tabs.

Broker quote workflow

Use when: The shipment is high-value or the classification is legally ambiguous.

Documented

  • Pairs duty estimates with broker review and entry-filing context.
  • Adds operational accountability for the entry.

Limits

  • Slower than self-serve tools for early sourcing and pricing checks.

Official sources to verify

Use these primary sources when a tariff decision needs legal, operational, or audit review.

USITC Harmonized Tariff Schedule searchCBP rulings and legal decisionsCBP Automated Commercial Environment

FAQ

What is the best import duty calculator for US imports?

It depends on the inputs you have and the layers you need to see. For a US estimate, use a calculator that accepts an HTS code or product description and itemizes base duty, Chapter 99 programs and customs fees. US Tariff Rates itemizes those layers; Flexport's simulator is free for up to 10 codes; USITC HTS is the official schedule text to verify against.

Can an import duty calculator replace a customs broker?

No. A calculator can speed up screening, quoting, and sourcing decisions, but complex classifications and high-value shipments should still be reviewed by a licensed broker or trade professional.

What inputs do I need to calculate import duty?

At minimum, you need the HTS code or product description, country of origin, and customs value. For landed cost, add freight, insurance, entry type, and any brokerage or handling assumptions.

Related guides and tools

HTS code lookupLanded cost calculatorBest landed cost calculators

Import duty calculators FAQ

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Import duty calculators FAQ

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