Is the desktop app safe to install even though it is unsigned?

Unsigned does not mean unverified: every release publishes a SHA256SUMS.txt so you can confirm your download is byte-for-byte the published build, and the source is open under the MIT license. The OS warning simply reflects the missing code-signing certificate, not a detected problem.

Does the app work completely offline?

Yes. The versioned ruleset ships inside the app and no network calls are made — lookups, stacked calculations and landed-cost math all run locally. Updates arrive as new releases you download, not as background syncs.

How do I update the tariff data?

Download the newest release from GitHub Releases or the download page; each release bundles the current ruleset snapshot. The Tariff Radar changelog tells you what changed between snapshots, and the app shows the data-as-of date with every result.

Will I get the same numbers as the website?

Yes — the app embeds the same us-tariff-lookup engine as the web calculator and the npm package, so the same input and ruleset version produce byte-identical results across all of them.

How much does it cost?

It is free, with no account and no usage limits, and open source under the MIT license.

US Tariff Lookup Desktop App: Download, Install and First Steps

Updated 2026-10-16Invoice × Tariff editorial

Who this is forAnyone who wants offline tariff lookup as a desktop app — freight forwarders, brokers and sellers working across machines.

Grab the installer for your platform from the download page or GitHub Releases, verify it against SHA256SUMS.txt, and expect a one-time unsigned-app warning on first launch (the steps to pass it are below). The app then works fully offline: search HTS codes in English or Chinese, stack MFN, Section 301/232 duties and MPF/HMF fees, and get a per-unit landed cost — identical numbers to the web calculator.

What you get

US Tariff Lookup for desktop is the whole calculator on your machine: HTS search in English or 中文, stacked duties (MFN base + China Section 301 + global 301 + Section 232/338), MPF/HMF entry fees and landed cost per unit. The versioned ruleset ships inside the app — no API key, no account, and no network calls, so it keeps working on a plane, in a warehouse or behind a corporate proxy. Windows, macOS and Linux, free and open source (MIT).

Download

Get the latest build from the download page or from GitHub Releases:

Platform	File	Requires
macOS (Apple Silicon)	`US-Tariff-Lookup-<version>-arm64.dmg`	macOS 11+
macOS (Intel)	`US-Tariff-Lookup-<version>-x64.dmg`	macOS 11+
Windows	`US-Tariff-Lookup-Setup-<version>.exe`	Windows 10+ (64-bit)
Linux	`US-Tariff-Lookup-<version>-x86_64.AppImage`	glibc x86_64

Verify the checksum (30 seconds, worth it)

Every release ships a SHA256SUMS.txt. On macOS or Linux:

shasum -a 256 US-Tariff-Lookup-1.0.0-arm64.dmg

On Windows (PowerShell):

Get-FileHash US-Tariff-Lookup-Setup-1.0.0.exe -Algorithm SHA256

The digest must match the line in SHA256SUMS.txt. Builds are not code-signed yet, which is exactly why the next section exists.

First launch: the unsigned-app warning

Because the builds are not code-signed yet, your OS shows a one-time warning. This is expected — here is the way through on each platform:

macOS: right-click the app → Open → Open in the dialog. If the dialog refuses, run xattr -dr com.apple.quarantine "/Applications/US Tariff Lookup.app" once in a terminal.
Windows (SmartScreen): click More info → Run anyway. The installer then proceeds like any other.
Linux: chmod +x US-Tariff-Lookup-*.AppImage once, then run the file (or make it executable from your file manager's properties dialog).

You only do this once per install; the warning does not reappear.

Your first lookup

Search — type a code prefix, English description or Chinese keyword ("6109", "cotton t-shirt", 保温杯). The curated set covers high-frequency HTS 8-digit codes with bilingual names.
Set the scenario — origin country, transport mode (sea / air / express / postal) and shipment value. HMF applies to sea freight; postal shipments at or under $2,500 use informal-entry flat fees.
Read the stack — every duty line shows its amount plus legalBasis and the official source (USITC / USTR / CBP / Federal Register); click through to verify any row.
Get the per-unit cost — the landed-cost panel spreads duties and fees across your units.

The interface is bilingual (English / 中文) and follows your system language.

Same numbers as everything else

The desktop app embeds the exact same us-tariff-lookup engine as the web calculator and the npm package — same input, same ruleset version, byte-identical output. One honest note, stated in the app itself: apart from the FY2027 fee table, most rate lines still carry sample/unverified flags, so treat results as planning-grade estimates, not certified entry data.

Updating

Data ships inside the app, so updates come as new releases: watch the GitHub Releases page, or check the Tariff Radar to see what changed and download the matching build. Prefer zero installs? The browser extension puts the same lookups in your toolbar.

Frequently asked questions

Is the desktop app safe to install even though it is unsigned?: Unsigned does not mean unverified: every release publishes a SHA256SUMS.txt so you can confirm your download is byte-for-byte the published build, and the source is open under the MIT license. The OS warning simply reflects the missing code-signing certificate, not a detected problem.
Does the app work completely offline?: Yes. The versioned ruleset ships inside the app and no network calls are made — lookups, stacked calculations and landed-cost math all run locally. Updates arrive as new releases you download, not as background syncs.
How do I update the tariff data?: Download the newest release from GitHub Releases or the download page; each release bundles the current ruleset snapshot. The Tariff Radar changelog tells you what changed between snapshots, and the app shows the data-as-of date with every result.
Will I get the same numbers as the website?: Yes — the app embeds the same us-tariff-lookup engine as the web calculator and the npm package, so the same input and ruleset version produce byte-identical results across all of them.
How much does it cost?: It is free, with no account and no usage limits, and open source under the MIT license.

Go to the download page

Installers for Windows, macOS (Intel and Apple Silicon) and Linux, with SHA256 checksums and all past releases.