Internet is slower on the PC?

Since today I receive with my laptop only 8 Mbit / s and if I try it in the same place with my iPad I receive 25.8 Mbit / s. Why?

Good news: the internet is not slower.

Bad news: It's the Wi-Fi hardware of your laptop. (If the antennas of both devices were actually at the same test position).

Disclaimer:
On this portal, many indicate incorrect or inaccurate units of measurement.
With you I now assume that you know what you are talking about and what you have measured. Otherwise, my answer would not be correct.