What it is
An embeddable widget that shows an estimated CO₂e figure for a shipping route — useful at checkout, on a product page, or in an order confirmation.
``html <iframe src="https://trackjet.world/embed/carbon?from=FRA&to=MAD&mode=air" style="width:100%;max-width:420px;height:200px;border:0" title="Shipping carbon estimate"></iframe> ``
Parameters: from and to (airport codes like FRA/MAD, or some City, CC forms), and mode (air, road, sea, parcel).
How the number is produced
It reuses TrackJet's carbon engine: great-circle distance between the two points, then a GLEC / ISO 14083-aligned factor for the transport mode. It is always labelled "estimated · great-circle" so no one mistakes it for a measured, audited footprint.
When it can't resolve a route
If a place name does not resolve to coordinates, the widget says "route not recognised" rather than inventing a distance. Airport and port codes resolve most reliably; bare city names sometimes do not (a dataset limit, stated honestly).
Why estimate at all
A directional, clearly-labelled estimate at the point of choice nudges better decisions (consolidate, choose ground over air) far more than a precise number nobody sees. The honesty of the label is the point — see the broader [carbon reporting](/docs/carbon-reporting) docs for the methodology.