Free US tariff lookup API by HS code or product name: base MFN rate, 2026 China stacked estimate (Section 301) and EU rate. No key required for the free tier.
Every feed has a free snapshot, no signup: pixharvest.com/try
Paid calls: $0.05 per change check, $0.50 per intel report, $0.03 per target in batch (up to 50), $5 landscape. Agents settle USDC on Base via x402 (0% commission); humans buy a key on /pricing.