01
Check a broker's entry
Compare the Chapter 99 lines on an entry with an independent stack, line by line, with the citation for each.
Duty Stack APIUS duty calculator and tariff API
The US duty on any HTS line, for any origin, with citations
Base rate plus every Chapter 99 line (Sections 301 and 232, IEEPA, Section 122 and others), the duty in dollars, the lines considered and not applied, and a citation for each.
- 1,671Chapter 99 rules
- 26,246HTS lines
- 2025-01-01to 2026-10-09, entry dates
Duty Calculator10 free calculations a day
Recorded answer of the real API on the current data for this sample.
HTS 6112.19.40.50 from CN, entered 2025-08-20
Total duty41%= $4,100.00 on $10,000.00
Not included
- Merchandise processing fee (MPF) and harbor maintenance fee (HMF)
- Antidumping and countervailing duties
- Duties on a specific (per unit) basis, which need the quantity
| Line | Rate | Running total | Duty |
|---|---|---|---|
| Base rate column 1 General | 3.5% | 3.5% | $350.00 |
| 9903.01.24 IEEPA | +20% | 23.5% | $2,000.00 |
| 9903.01.25 IEEPA | +10% | 33.5% | $1,000.00 |
| 9903.88.15 Section 301 | +7.5% | 41% | $750.00 |
| Total duty | 41% | $4,100.00 |
We do not classify goods. These pages show reference rates for HTS codes. Choosing the code for an entry is the importer's responsibility, and entries are filed by the importer of record or a licensed customs broker. Duties shown are calculations from public sources, not legal advice.
Products
One key and one plan for all of them. In the browser (10 free calculations a day), as an API and as an MCP server. Fees, antidumping and countervailing duties are not included.
HTS code, origin, entry date and value in: the US duty stack (base rate and Chapter 99 lines) and the duty in dollars out, in the browser.
/calculator/10 free calculations a day
The base rate plus every Chapter 99 line for an HTS code, origin and entry date, with citations and the duty in dollars.
POST/v1/tariffs/duty-stack10 units
The tariff schedule as of any date: lines, base rates, revisions, changes and the Chapter 99 measures that reach a code.
GET/v1/tariffs/hts/search
?q=cap+screws &limit=51 unit Entry lines in: the refundable IEEPA amount and the CAPE route for each line out.
POST/v1/tariffs/ieepa-refund10 units per line
Every dated change to Chapter 99 measures, HTS lines and base rates, as a feed you can poll.
GET/v1/tariffs/changes
?since=2026-09-01 &limit=201 unit Duty stacks, HTS lookups, measures, refunds and the change feed as tools for AI agents.
POST/mcpsame units as REST
The effective-dated dataset and bulk files for embedding and research (a daily delta feed is coming soon).
GET/v1/datasets/tariffs/snapshot
Owed IEEPA refunds?
Paste or upload your entry lines and get the refundable IEEPA amount and the CAPE route for each line: free refund estimator (with a free key), or the IEEPA Refund API for large files.
Examples
One engine behind three jobs: checking an entry, quoting before an order, and tariff data inside software.
02
Quote landed duty before you order
Enter the HTS code, origin, date and value; see the duty in dollars, or compare origins side by side.
Duty Calculator
03
Embed US duty stacks in your software
One call returns the stack as data with the dataset version, so your tool can pin and diff it.
Duty Stack APICoverage and freshness
Data as of 2026-10-09: entry dates 2025-01-01 to 2026-10-09, HTS releases 2025HTSBasic to 2026HTSRev21.
- 1,671Chapter 99 rules
- 26,246HTS lines (headings to statistical lines)
- 55HTS releases
- 5,692rule citations
- 20,427base-rate intervals
Latest changes
| Date | Change | Measure or line | Source |
|---|---|---|---|
| 2026-09-29 | HTS line established | 9903.04.70 | USITC HTS Change Record |
| 2026-09-29 | Chapter 99 9903.03.12 starts | Other Chapter 99 | Proclamation 11064, 91 FR 58331 (Sep 14, 2026) |
| 2026-09-29 | Chapter 99 9903.03.13 starts | Other Chapter 99 | Proclamation 11047, 91 FR 46653 (Jul 23, 2026) |
| 2026-09-29 | Chapter 99 9903.03.14 starts | Other Chapter 99 | Proclamation 11065, 91 FR 58339 (Sep 14, 2026) |
| 2026-09-29 | Chapter 99 9903.04.60 starts | Section 232 | 2026HTSRev21 heading 9903.04.60 |
How we check
Two independent AI passes read the primary sources, disagreements are settled against the source text, and code copies every rate, date and HTS code. Code checks run on every release; results that need an expert carry a review flag.
How we check accuracyReference pages
Every HTS heading, with its duties by origin
1,228 headings, each with its base-rate range and the additional duties for the main origins on 2026-10-09. The duty on each of the 19,831 statistical lines, for any origin and entry date and with citations, is in the free calculator and the API.
Pricing
Free: 2,500 units a month (250 duty stacks) for every product. Developer $49 a month, Pro $249 a month.
Tariff Data Licensing
The effective-dated dataset and bulk files for embedding and research (a daily delta feed is coming soon). Bulk files and enterprise terms, or write to support@htscalculator.com.