Calculator notes and instructions.
The three modes:
- Time to charge to %: just fill in the initial charge percentage and the desired charge level.
- Time to charge (and charge %) to have a desired range.
- Time to charge (and charge %) to add desired additional range.
Time is currently minutes, not minutes and seconds.
I have significant analysis of EVs in general, and some of the Atto 3 in specific, as I feel it represents the start of a 3rd wave of EVs. As I get more data, I will update calculations.
All charge times are best case scenarios, as many things can delay charging, including the charger breaking down as you go to use it, or someone else plugging in to the only available charger just as you arrive.
Apps like a better route planner have built in calculations, but these do not always match people experiences with vehicles, particularly newly released vehicles. This calculator allows modifying the charge curve data to get result consistent with a person’s experience. Plus it is easy to calculate times for alternative plans, and use together with other route planning.
This is a first version, and will adapt to feedback. I suspect it is slightly optimistic, as currently only calculates time under ‘ideal’ circumstances. Plus there is the time for plugging in an getting the charger started to be added.
Atto 3 Charge ‘Curve’.

It is not clear if this data is ‘charge added’, or ‘power to the battery’, or even power sent from the charger.
In all cases there will be some losses. The ‘losses’ field can be adjusted to allow for this.
Further, this curve is under ideal conditions. As noted on the Atto 3 page, people have recorded very different charge curves in extreme temperatures, or on chargers with more real world constratiants.
Updates.
- *2022 September 28: Added charge loss calculations and moved loss setting to 1st page.
- 2022 September 27: Initial version.
Features to be added:
- Ability to save charging curves for different vehicles.
- Currently assumes >= 150kW charger, other charger options to be added.
If people find this useful, please indicate with likes (page top right), and then I will keep updating.