Calculate shipment weight and volume API

Sum supplied package weights and calculate volume from centimetre dimensions. Volumetric weight is calculated only when the request includes a divisor.

The Calculate shipment weight and volume operation is part of the Freight & Customs API on BRAINIAC.software. Sum supplied package weights and calculate volume from centimetre dimensions. Volumetric weight is calculated only when the request includes a divisor. It is exposed as POST /api/v1/freight-customs/shipment-weight-volume-calculate and priced at $0.03 USDC on Base. Payment uses the x402 exact scheme: an unpaid call returns HTTP 402 with payment requirements; after paying the exact USDC amount, retry the same request with a payment-signature header and Idempotency-Key. No account and no API key are required. Data sources for this product: The shipment documents and fields supplied in the request. UK Trade Tariff public search for commodity candidates. Limitations: No customs declaration is submitted and no shipment is booked. Duty rates, restrictions, sanctions status, and country-specific requirements are not invented. HS code suggestions are candidates from the public UK Trade Tariff, not a classification. Text is read from text-based PDFs and plain text. Scanned pages are not OCR-read. Outputs are compliance prechecks, drafts, or data lookups for human review. They are not official determinations, legal advice, identity confirmation, or certified filings. Related operations in this group include Extract a shipping document, Validate a commercial invoice, Validate a packing list, Extract a bill of lading. Open the group documentation for the full request schema, field notes, and response examples before integrating.

POST$0.03 USDC
/api/v1/freight-customs/shipment-weight-volume-calculate

Example request

curl -i -X POST "https://www.brainiac.software/api/v1/freight-customs/shipment-weight-volume-calculate" \
  -H 'content-type: application/json' \
  -H 'Idempotency-Key: <fresh-64-character-random-hex-key>' \
  --data-binary @- <<'JSON'
{
  "packages": [
    {
      "description": "Carton",
      "count": 2,
      "lengthCm": 40,
      "widthCm": 30,
      "heightCm": 20,
      "netWeightKg": 8,
      "grossWeightKg": 10
    }
  ],
  "volumetricDivisor": 167
}
JSON

An unpaid probe returns HTTP 402 with x402 payment requirements. After paying the exact USDC amount on Base, retry the identical request with a payment-signature header.

FAQ

  • Do I need an API key? No. Pay the listed USDC amount with x402.
  • What network? Base (eip155:8453), USDC.
  • Is this an official determination? No. Results are for human review against the cited sources.

Related APIs

Freight & Customs APIFull docsHow it works