Guides
The honest answer first, how to check it yourself in Activity Monitor second, and how Hedroom does it third.
Why your Mac says memory is full (and why that's fine)
A Mac that uses nearly all its memory is doing its job. Here is how to tell normal from trouble, and what to check first.
Memory pressure vs used RAM
Why the colored graph in Activity Monitor tells you more than the 'Memory Used' number, and how to read it.
What swap is and when it hurts
Swap is macOS borrowing disk space to hold memory. A little is normal. Here is how to tell when it is costing you speed.
Why RAM cleaners make Macs slower
What 'free memory' buttons actually do, why the effect is the opposite of what you want, and a test you can run on your own Mac.
Find the app that's slowing your Mac
A step-by-step way to find the app behind a slow Mac using Activity Monitor: memory first, then CPU, then energy.
kernel_task, WindowServer and other processes explained
What the macOS processes at the top of Activity Monitor do, why they sometimes use a lot of CPU, and what you can and can't do about it.
What starts with your Mac and what it costs
Login items, launch agents and background helpers all start when you log in. Most cost very little. Here is how to see which ones cost something.
Is your external display making your Mac work harder?
Scaled resolutions, high refresh rates and several screens all give WindowServer more to draw. How to check, and what changing it can and cannot do.
Fan control on a MacBook Pro: what's safe
macOS already runs your fans. What changing a fan curve can do, what to avoid, and what Hedroom does to keep it safe.
Will a local AI model fit in your Mac's memory?
A rule of thumb for how much memory a local model needs, why context length matters, and what limits the GPU on an Apple Silicon Mac.