The US duty and tariff API for landed cost.

One REST call returns the fully-stacked rate for any HTS code and country of origin, resolved in the right legal order.

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Not a developer? Look up any code in the dashboard.

Used in production by importers, customs brokers, and supply-chain platforms.

How it works

From signup to first call
in under 10 minutes.

Get an API key

export TARIFFS_API_KEY=sk_live_...

Call `/resolve`

Pass an HTS code and country of origin. Get base duty plus every applicable Chapter 99 measure stacked in the right legal order.

GET /api/v1/tariffs/resolve?hts=…&origin=CN

Show landed cost

Drop the resolved rate into your checkout, cart, ERP, or quoting flow. JSON in, money out. Use as_of for historical rates.

duty = value * total_resolved_ad_valorem_rate

swipe

What's covered

Every layer of the US tariff stack. One source of truth.

Full data schema

HTS · Base rate

Harmonized Tariff Schedule

All 17,000+ 10-digit subheadings. Column 1 General, Column 1 Special (FTAs), Column 2.

Section 301 · New

China lists + forced-labor duty

China Lists 1-4A and exclusions, plus the country-wide forced-labor duty that added ~55 origins on 24 July 2026.

Section 232

Steel, aluminum, derivatives

The merged 2026 metals regime plus autos, trucks, timber, and semiconductors. Country quotas and exemptions included.

IEEPA · Ended

Struck down Feb 2026

The Supreme Court held IEEPA does not authorise tariffs. Not applied to a current lookup; the country and product scope stays readable by as_of date, for refund research.

Chapter 99

Modifiers & overrides

Every Chapter 99 subheading that layers on top, with stacking order respected.

Section 201

Safeguard quotas

Quartz surface products under Proclamation 11051, in-quota and over-quota lanes, with the quota year step-down modeled.

Section 338 · New

An additional 50% on Canadian autos, alcohol, and dairy under a 1930 authority last used in the 1940s. Scope modeled from the proclamation annexes, so as_of queries on or after 22 August 2026 return it.

CN China · 301 lists + forced labor VN Vietnam · 301 forced labor CA Canada · USMCA · 338 from 22 Aug 2026 MX Mexico · USMCA IN India · 301 forced labor KR Korea · KORUS · combined cap JP Japan · combined cap DE Germany · EU combined cap BR Brazil · 301 country-wide + forced labor TH Thailand · 301 forced labor

For developers

The tariff API — one endpoint, deterministic JSON.

GET /api/v1/tariffs/resolve?hts=…&origin=… returns the base duty, every applicable Chapter 99 measure, a confidence score, and attempted candidates when the match isn't exact. Bulk endpoint accepts up to 200 codes per request. REST + JSON. No SDK required.

Read the docs Try /resolve →

GET /api/v1/tariffs/resolve?hts=8541.10.00.80&origin=CN

// deterministic, no AI guessing
{
  "hts": "8541.10.00.80",
  "origin": "CN",
  "match_type": "exact",
  "match_level": "10",
  "confidence": 1.0,
  "base_duty": { "rate": "0%", "rate_type": "general" },
  "additional_measures": [
    { "program": "Section 301", "rate": "50%", "chapter_99_ref": "9903.91.05" }
  ],
  "warnings": [],
  "attempted_candidates": []
}

Pricing

Public pricing. Start today.

14-day free trial. Card required at signup, cancel any time before day 14 and pay nothing. White-label, reseller and high-volume terms are priced on a call.

For a few lookups a day · API + AI

Starter

$99 /mo

✓1,000 API calls per month
✓Single /resolve endpoint
✓Section 301, 232, 338, Chapter 99 stacking
✓Historical rates with as_of
✓Confidence scores, warnings, match metadata
✓25 saved HTS codes
✓Duty calculator
✓Bulk CSV import with column mapping
✓1 team seat
✓100 AI assistant messages / mo
✓Standard rate limits

Start 14-day free trial

Card required · cancel before day 14

Verified at every step.

Every rate we publish is pulled from official US trade publications, kept beside its raw source, audited by a separate AI pass, and re-tested before it ships. Traceable, audited, continuously tested.

1

Ingestion Pulled from source

Pulled directly from official publications. No spreadsheets. No scraping third-party sites. Every source row is preserved exactly as published.
2

Source archive Kept unchanged

Raw kept beside structured. Tagged to a numbered revision. We can reconstruct the rate on any past date.
3

Structured parse Made machine-readable

Raw duty text becomes structured rates. Every parsed value records how it was derived. Clean extractions stand apart from anything that needs review.
4

Independent audit Second pass, AI

A separate AI re-reads the source. Anything that does not match what we published gets flagged. Not the same system checking its own work.
5

Regression tests Caught before ship

Known lookups re-run on every update. Any failure is caught before it reaches a single customer.

The trust trail

Every rate is provable, audited, and continuously tested.

Stake a customs filing on it. We keep the receipts.

Live freshness layer

All systems green Synced 15 hours ago Audit pass rate 94.41% API lookups today 218

USTR · trade remedies CBP · CSMS & rulings ITC · HTS revisions Federal Register

How we source and verify data →

Recent updates

Full changelog →

Oct 09

HTS 2026HTSRev21 imported

USITC published 2026HTSRev21 and it is now live in the API.

Import
Oct 06

Section 232 pharmaceuticals now show the patent condition

From September 29, 2026, the Section 232 duty on the pharmaceutical provisions listed in U.S. note 40(c) depends on whether the article i...

Regulatory
Oct 03

Brazilian heavy drones: 25% Section 301 duty now added on top of the Section 232 drone duty

From September 3, 2026, heavy unmanned aircraft from Brazil under subheadings 8806.24.00, 8806.29.00, 8806.94.00 and 8806.99.00 owe the 1...

Regulatory
Oct 03

Canada: alcoholic beverages, dairy-list products and motorcycles over 800 cc excluded from importation from 2026-09-29

Proclamations 11061, 11062 and 11063 exclude from importation into the United States products of Canada under 68 tariff provisions, for g...

Regulatory
Oct 02

New zero-duty heading for pharmaceuticals used in clinical trials and research

Commerce corrected the Section 232 pharmaceutical tariff schedule from September 29, 2026. Pharmaceutical articles and ingredients used s...

Regulatory

Questions, answered

You ask. We answer.

Can I calculate tariffs programmatically?

Yes. GET /api/v1/tariffs/resolve takes an HTS code and country of origin and returns the base duty plus every applicable Chapter 99 measure with rates, effective dates, and confidence scores. Bulk endpoint handles up to 200 codes per request. Pass as_of for historical rates. See /api-documentation.

Where does the data come from?

Every rate returned by Tariffs API comes from the official US Harmonized Tariff Schedule published by USITC, combined with USTR, CBP, and Federal Register notices for the Chapter 99 trade measures, including ones that have since ended. We never invent numbers.

How often is it updated?

Base HTS data is refreshed weekly against USITC's published schedule. Chapter 99 and trade-measure updates are captured daily from USTR and CBP notices. Breaking changes (new Section 301 rounds, new Section 232 or Section 338 proclamations) are applied within 24 hours of publication.

Which trade measures do you cover?

Section 301 (China), Section 232 (steel, aluminum, autos, semiconductors) and Section 338 (Canada) are resolved and stacked correctly on top of base HTS rates. Chapter 99 reference codes are resolved to numeric rates when available. Measures that are no longer in force, including the IEEPA tariffs and the Section 122 surcharge, are not applied to a current lookup; pass an as_of date inside the period they were in force and the historical rate is returned.

How does the 14-day free trial work?

Sign up with email and a card. You get full access to the API and every endpoint for 14 days. Cancel any time before day 14 and you're not charged. After day 14 the plan is $199/month. No long-term contract, cancel from the customer portal at any point.

What are the rate limits and infrastructure?

Pro is 500 requests per minute. Bulk /resolve handles up to 200 HTS per request with deduplication and caching, so a single bulk call counts as one API call against your monthly quota. Served from US-East on PostgreSQL with Redis caching. Enterprise customers get a contractual SLA.

How should I interpret the confidence score?

Every resolved measure includes a confidence score and a match type (exact, prefix, inherited). High confidence means the HTS code matched a measure directly. Medium or low means we inferred the match from a parent heading or a normalized variant — the JSON response includes attempted_candidates so you can verify. For anything low-confidence, cross-check with your broker or CBP.

Does Tariffs API replace a customs broker?

No. Tariffs API gives you accurate rate data and landed-cost calculations, but does not file entries, issue binding classification rulings, or act as a customs broker. Use it for checkout pricing, catalog pricing, compliance planning, and audit trails. Final classification and entry filing should go through a licensed customs broker.

Is this legal advice or a binding classification?

No. Data is for informational purposes. Final classification and duty determinations are made by US Customs and Border Protection (CBP). For binding rulings, request a CBP ruling letter. We tell you what the schedule says — CBP tells you what applies to your specific entry.

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Ship landed cost at checkout this week.

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