Cruise altitude

[Samet_Ozturk]

I was wondering how the pilots decides the cruise altitude. Does it depends on weather or the distance?

[USA007]

Pilots don’t really decide ATC does. Pilots can request a Flight Level but that jurisdiction comes down to ATC clearance.

[Eric_Jordy]

All of the above so far. A flight plan may call for a cruise altitude of 30,000 feet, however weather, distance, traffic, and ATC all have a say. The pilot can request a different altitude to try and find calmer airspace, but still needs ATC clearance.
In real world aviation there are very few moments where ATC isn’t giving you instructions. And even if they aren’t, pilots still need to check in.

[Flightfan84]

Also will vary by the direction you’re travelling. 0-180 degree bearing will fly one altitude, 181-360 degree bearing will fly another, the difference being odd or even numbers.