# MyCO2 Suite — Flight Emissions API

> The flight endpoint calculates great-circle CO₂e for a journey by airport (IATA / UN-LOCODE) or lat-long, cabin class and passenger count, with optional radiative forcing. Factors follow the UK BEIS/DESNZ 2025 methodology; the response returns per-passenger and total emissions with distance and haul type.

Endpoint: POST https://api.myco2suite.io/v1/flight
Price: $0.003 / call (from the first call). Pay with an API key (x-api-key) or, with no signup, via x402 pay-per-call in USDC on Base — a keyless request returns HTTP 402 with machine-readable payment requirements.
Free tier: 1,000 calls/month with a key (get one at https://myco2suite.io).

## Inputs
- origin (required): IATA (LHR) or UN/LOCODE; or origin_lat + origin_lon
- destination (required): IATA (JFK) or UN/LOCODE; or destination_lat + destination_lon
- cabin_class (optional): economy | premium_economy | business | first
- passengers (optional): Passenger count (default 1)
- include_radiative_forcing (optional): Add the RF multiplier (default false)

## Example request
POST https://api.myco2suite.io/v1/flight
Header: content-type: application/json
Header: x-api-key: <your key>   # or pay per call via x402 (no key)
Body: {"origin":"LHR","destination":"JFK","cabin_class":"economy","passengers":1}

## Example response (JSON)
{
  "co2e_kg": 986.4,
  "per_passenger_kg": 986.4,
  "flight": {
    "gcd_km": 5541,
    "haul_type": "long_haul"
  },
  "factor": {
    "unit": "gCO2e/passenger.km",
    "source": "BEIS 2025",
    "licence": "OGL v3.0"
  }
}

Every response is methodology-stamped: it includes the exact factor value, unit, source, licence, data year, gas basis (CO2 vs CO2e) and GWP version used.

## Common use cases
- Business-travel carbon reporting (Scope 3.6)
- Add flight footprints to booking and expense tools
- Let a travel agent compare routes by CO₂e before booking

## Related capabilities
- https://myco2suite.io/carbon/freight (freight)
- https://myco2suite.io/carbon/activity (activity)
- https://myco2suite.io/carbon/transaction (transaction)

## Links
- Human page: https://myco2suite.io/carbon/flight
- Full API docs: https://myco2suite.io/docs
- Full agent/LLM docs: https://api.myco2suite.io/llms.txt
- Code examples: https://github.com/Jaws22/myco2-examples
- MCP server: https://api.myco2suite.io/v1/mcp (registry: io.myco2suite/carbon-intelligence)
- Contact: admin@myco2suite.io