Our Methodology

Freight quotes are a real money decision for importers, e-commerce sellers, and relocating families. You deserve to know exactly how our cost and transit figures are assembled, what they represent, and where they fall short of a live carrier quote.

What our figures represent

Use our figures for rough planning, cross-country comparison, and deciding between air and sea. For any shipment you're about to book, get a live quote from the carrier you intend to use.

How we build the baselines

Each country entry combines several inputs that together approximate a realistic industry baseline:

1. Published carrier tariff sheets.DHL, FedEx, UPS, and regional integrators publish zone-based rate tables for both express and standard services. We anchor per-kg air freight to these published zones for the country's region.
2. Freight rate indices. For sea freight we lean on public container-rate indices such as the Freightos Baltic Index and the Drewry World Container Index, normalized to a per-kg basis for general cargo.
3. World Bank Logistics Performance Index. The World Bank LPI benchmarks each country's customs, infrastructure, tracking, and on-time performance. We use this to adjust transit-day expectations for destinations with slower customs clearance or last-mile delivery.
4. UNCTAD maritime statistics. The UNCTAD Review of Maritime Transport provides the authoritative annual overview of container shipping capacity, port throughput, and major-route rate trends.

Customs and duties

Our country pages link out to TariffPeek for HS code classification and duty rates, because the right duty for your specific product depends on classification that changes across product families. The foundational customs references we rely on are:

• World Customs Organization (WCO) — the authoritative source for the Harmonized System (HS) codes used worldwide for tariff classification.
• US Customs and Border Protection — the authoritative US import reference, including Section 321 de minimis rules and Section 301 tariff actions.
• International Trade Administration (ITA) — US Department of Commerce resource for trade agreements, export controls, and FTA lookups.
• Incoterms 2020 (ICC) — the international standard that defines who pays for freight, duties, and insurance at each stage of an international shipment.

Air vs sea decision framing

The air-vs-sea choice is the single most impactful decision you make on an international shipment. Our rule-of-thumb breakdown (widely accepted in the industry, though not universal):

• Under ~10 kg— air freight almost always wins on landed cost, because small-parcel sea handling has high fixed overhead.
• 10 – 100 kg— depends on urgency and product value. High-value or time-sensitive goods go air; bulky or low-margin goods go sea.
• Over 100 kg, not urgent— sea freight (typically LCL, less-than-container-load) wins decisively on per-kg cost, at the price of 3–8 extra weeks of transit.

Update frequency

Freight rate indices update weekly to monthly; carrier tariff revisions happen annually with mid-year fuel surcharge adjustments. We refresh our baseline tables quarterly and immediately when a major shift (e.g., capacity crunch, Red Sea disruption) changes the underlying indices meaningfully.

Limitations you should know about

• No live rate lookups. Our numbers are planning figures, not quotes. A freight forwarder will always give you a tighter number for an actual shipment.
• No volumetric weight modeling. Carriers charge by the greater of actual and volumetric weight. Large, light packages cost much more than the per-kg figures suggest.
• No duty calculation.Our cost columns are freight-only. Duties, VAT, GST, and broker fees can add 5–25% or more on top depending on product and destination.
• No carrier-specific quirks. USPS, Canada Post, Royal Mail, Japan Post, and similar national postal services price very differently from the integrator carriers. Our baselines assume commercial integrator pricing.
• Not logistics advice. Nothing on ShipCalcWize constitutes professional logistics, customs-brokerage, or legal advice. For shipments with real money on the line, work with a licensed freight forwarder or customs broker.

Corrections and feedback

If a published carrier rate or official index disagrees with a figure you see here, please contact us with the source and the number. Corrections from the community are the fastest way we improve the dataset.

This methodology page was last reviewed in March 2026. Material changes to how we source or compute the data will be reflected here before they reach production pages.