A useful result should be reproducible.
The tools do not reproduce supplier billing systems.
Units
kW is power, kWh energy, p/kWh a unit rate and p/day a standing charge.
Bill layers
Electricity, gas, standing charges and equipment use are not hidden in one rate.
References
Defaults are dated, editable examples rather than offers.
Sources
Ofgem and GOV.UK are prioritised.
Limits
Region, tariff, meter, weather, debt and support require individual checking.