Where infrared.city fits
3,204,804 simulations run on Infrared Core (as of 29 Oct 2026).
infrared.city runs 12 models from one engine, Infrared Core, among them wind, wind comfort, sun, daylight, radiant heat and felt heat (UTCI). It works on real 3D building and terrain meshes, in a browser app, through an API and SDK, and in plugins for Grasshopper, QGIS and ArcGIS. Felt heat for 1 km² takes about 5 s once the geometry is uploaded, and 400 km² took 44 s as four 100 km² runs in parallel. Run times are not like for like across tools: area, grid, simulated hours and physics differ. Sun, sky and radiant heat come from ray tracing. Wind comes from an AI model trained on CFD results, not from a CFD run for each request. The live layer runs a whole city every hour on a forecast. It is a climate layer: it brings the simulation results, not the twin itself.
- You need felt heat, wind comfort, sun and daylight for the streets and buildings in a twin.
- You need the results from an API and SDK, for many design options.
- You need an hourly city layer on a weather forecast.
Use both
Both sides offer APIs. A twin application can request climate results from the infrared.city API like any other client, and show them next to the infrastructure data.
Facts side by side
| infrared.city | Bentley iTwin | |
|---|---|---|
| Runs as | Cloud: browser app, API and SDK, plugins | Cloud platform with APIs, SDKs and sample applications |
The infrared.city values repeat the full comparison. Each value for Bentley iTwin comes from the sources below.
Sources
- Bentley: iTwin platform , accessed 30 Oct 2026.