MacBook Air handles it fine, but you can still do better.

Yes, it’s designed to handle it.

Modern MacBook Airs (2018 and later) have a feature called Optimized Battery Charging. It learns your routine and holds the charge at 80% until right before you usually unplug. So if you leave it plugged in at 100% all day, the laptop already stopped charging before it got there. Apple isn’t stupid.

The real enemy is heat and leaving the battery at full voltage for months on end. If your MacBook Air lives on a desk and you never move it, the battery will still age slowly, but not because of the charger. The built-in battery management is good enough that most people never need to think about it.

If you want to be extra nice to the battery, use a tool like Aldente or Battery Toolkit to cap charge at 80% manually. But honesty hour: for the typical user who plugs in at night, the difference is negligible. You’ll replace the laptop before the battery fails.

Spend your worrying on something that matters.