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 importers · no code

Importer

$99 /mo

✓Unlimited watched HTS codes
✓Change alerts by email when a rate moves
✓Duty exposure totalled across your codes
✓Section 301, 232, 338, Chapter 99 stacking
✓Historical rates with as_of
✓Terminal: live lane monitor and expiry calendar
✓Tariff sheet PDF for any code
✓Bulk CSV import with column mapping
✓15 AI assistant messages / mo
✓No code required

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 8 hours ago Audit pass rate 94.41% API lookups today 140

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

How we source and verify data →

Recent updates

Full changelog →

Sep 11

Unmanned aircraft (8806): two possible Section 232 duties, no single total

For six unmanned aircraft subheadings (8806.21, .22, .23, .91, .92 and .93) from any origin other than the United States, the Section 232...

Regulatory
Sep 07

Brazil Section 301: note 50 exemptions now applied (9903.05.03)

Brazilian-origin goods on the U.S. note 50(a)(ii) exemption list (864 tariff lines, heading 9903.05.03) were being charged the 25% Sectio...

Regulatory
Sep 07

Guatemala and El Salvador now receive their DR-CAFTA duty-free rate

Goods originating in Guatemala and El Salvador were being quoted the Column 1 general duty rate instead of the DR-CAFTA preferential rate...

Regulatory
Aug 30

Canada Section 338 duties: start date corrected to August 22, 2026

Proclamation 11056 temporarily suspended the Section 338 duties on Canadian alcohol, dairy, and motor vehicles, moving their start from A...

Regulatory
Aug 26

2026 Review of Notorious Markets for Counterfeiting and Piracy: Comment Request

Verdict: NO DATA IMPACT — USTR comment request for the 2026 Notorious Markets List review (Special 301 IP program, 19 USC 2242); no tarif...

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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