How long does laptop battery last?

I bought a laptop 3 days ago (Dell xps 9730) and this model is popular because it is small, compact and durable (in terms of battery life).

I have now bought this model at a greatly reduced price because it was the exhibit…

I now have the feeling that the battery is all faster than it should.

It has a 52Wh battery and I can watch a live stream and see how quickly the battery runs out…

How can I assess whether the battery is still intact or lasts long enough

I lose 7% in about 30 minutes of watching live stream (on low quality)

If I'm not mistaken, there's a tool from Dell to test the battery.

If you extrapolate the 7% you could 14x7 = 98%, i.e. 14x 30 min. = Watch the live stream for 7 hours, that's sensational! Some batteries are empty after 1.5 hours on laptops. It will probably go faster and faster towards the end of the battery draining, but at least you can be satisfied, I mean.

You can't calculate that exactly, but you can try mixed operation and a stopwatch to find out when the battery is empty.

In an exhibition, the device will probably always have run on a power supply, do not think that the battery was challenged there.