No need to do any math. If you have a genuine Apple charger the first line on the side (narrow side opposite of cable going to laptop) will state 85W MagSafe 2 Power Adapter.
- Answered by Russell D from Baton Rouge
- 20 Feb. 2020
- Flag as inappropriate Answer (how do you tell the difference between a 60-watt charger and an 85-watt charger?)