Data Sources

UN Comtrade

What: Reporter-submitted customs data for goods trade, covering 200+ countries since 1962.

Access: Free via comtradeapi.un.org. Premium tiers available for bulk downloads.

Rate limit: 500 requests/day on the free tier. Our ETL is scheduled daily and prioritizes G20 countries, major bilateral pairs, and commonly queried HS2 chapters.

Known caveats:

• Most recent year is preliminary — final revisions typically come 6–18 months after the year ends.
• Import values are CIF (cost, insurance, freight); exports are FOB (free on board). Importer and exporter totals for the same flow will differ by transport and insurance costs.
• Re-exports (goods transiting through entrepôts like Singapore, Hong Kong, Netherlands) can cause double-counting at the global level.
• Some countries (notably a handful in Africa and Central Asia) report intermittently.

World Customs Organization — Harmonized System

What: Reference data — 97 HS2 chapters (01–97), ~1,200 HS4 headings, ~5,400 HS6 subheadings.

Updated: Every 5 years — HS 1988, 1996, 2002, 2007, 2012, 2017, 2022.

Access: Public reference data, freely available.

Our current sample

The site currently contains a representative sample: 30 major trading countries × up to 20 partners each × 20 top HS2 chapters × 5 years (2020–2024), plus an HS4 slice for the top bilateral pairs. This gives you working pages end-to-end — real calculations, real pre-aggregations — while we progressively expand coverage via the daily Comtrade ETL. Countries and products outside the current sample will show empty tables; this is a known state, not an error.

What TradeFlowLookup does NOT cover

• Services trade (finance, travel, IP licensing) — we only cover goods.
• Informal cross-border flows and smuggling.
• Unit values and tariffs (those are in WITS and TRAINS databases).
• Sanctions-driven trade (some flows are intentionally unreported).