After re-stacking US tariff math in a spreadsheet 5 times in a year, I built the calculator I wanted

Hey IH 👋

Quick context: I run a small cross-border eCom side project sourcing

electronics from Asia. After the April 2026 reciprocal tariff round

dropped, I spent half a Sunday in Google Sheets re-stacking duty math

for the same 12 SKUs across 4 alternative origins (China vs Vietnam

vs Mexico vs India).

Then I realized I'd done variations of this exact spreadsheet five

times in the past year — every time a Federal Register notice changed

something. So I shipped DutyLane: https://dutylane.com

## The problem with what's already out there

Three categories of existing tools, none of them work for me:

1. SimplyDuty / Avalara — paywalled per query, opaque about which

USITC revision they're on. Fine for one-off shipments, painful for

ongoing sourcing decisions.

2. Flexport / customs brokers — enterprise sales cycle. I'm a

side project, not a Series B logistics co.

3. USITC's own site (hts.usitc.gov) — has the raw data, but no

calculator, no Chapter 99 (Section 301 / IEEPA / reciprocal)

overlay, no Federal Register reconciliation. You're on your own.

So DutyLane stitches the gap: type a product description or HTS code

→ get the stacked rate (MFN + Section 301 + IEEPA + reciprocal) →

compare across alt origins → every number is clickable back to its

USITC row or Federal Register notice.

## Stack (for the curious)

- Cloudflare Workers (SSR) — TTFB ~85ms from the nearest edge

- D1 — full HTS schedule, 11K+ rows

- R2 — daily snapshots for audit trail

- Vectorize + Workers AI — semantic search ("iPhone case" → top

HTS candidates with confidence scores) using BAAI/bge-m3 embeddings

- No JS framework on the page, just SSR HTML — Lighthouse 95+ across

the board

Total infra cost so far: $0/month (Workers free tier covers it).

## On monetization (the IH question 😄)

The calculator + lookup will stay free forever. I genuinely think

small importers shouldn't have to pay $0.50/query to know what they

owe.

The eventual paid tier I'm thinking about:

- SKU portfolio tracking — get pinged when a Federal Register

notice affects YOUR specific HS codes

- AD/CVD coverage — these need case-by-case research; a research

service makes more sense than a "calculator"

- API access for ERP/3PL integrations

But I want to validate demand before building any of that.

## What I'd love feedback on

1. Is the duty breakdown UX actually understandable? (Try

"lithium battery" or any product description on the homepage)

2. For those of you doing cross-border eCom — what data point would

make this go from "useful" to "I check it weekly"?

3. Any of you faced AD/CVD pain? Worth building paid coverage, or

too narrow?

4. The semantic HTS search is powered by Workers AI — would any IH

indie devs want a writeup of how that pipeline works?