Mac Running Hot and MacBook Fan Loud: How to Find the Process Behind the Heat
Mac running hot or fans staying loud? Check CPU, GPU, energy use, ventilation, and hardware symptoms to narrow down the cause.
5 guides
CPU, GPU & fan noise
Trace high resource use, heat, and loud fans to the right workload. Start with what you can observe, then follow the relevant process guide.
Start here
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The Mac is hot or the fan is loud
Check CPU and energy use first. If the load is low, the guide also covers ventilation, surroundings, and hardware symptoms.
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The problem follows a window or display
Investigate WindowServer and graphics-heavy apps. Compare the load as you close windows or change the display setup.
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kernel_task is at the top
Read what its CPU figure represents before taking action. Follow the thermal troubleshooting path instead of trying to terminate the kernel.
Read the guide →
Suggested reading
Work through the guides that match your situation, in the order below.
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WindowServer High CPU on Mac: What It Is and How to Fix It
WindowServer at 100%+ CPU? It is the macOS process that draws every pixel on your screen. Learn why it spikes, when to worry, and how to find the app actually causing the load.
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kernel_task High CPU on Mac: What It Is and How to Fix It
Seeing kernel_task in Activity Monitor? Learn what PID 0 means, why high CPU protects an overheating Mac, and how to find the real process causing it.
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mds_stores High CPU on Mac: When to Wait and When to Fix It
mds_stores eating CPU and disk? It is Spotlight's per-volume indexer. Most spikes are real work that resolves on its own — learn how to tell legitimate indexing from a stuck process, and what actually fixes it.
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Mac Running Slow? How to Find and Kill Resource-Hogging Processes
Step-by-step guide to diagnosing a slow Mac — find processes causing high CPU, memory pressure, and disk I/O, then kill or manage them with the right tool.
Tutorials Productivity
Tools for your investigation
Start with Activity Monitor
Use Apple’s built-in tool for an initial check. Its official guide explains the available views and measurements.
Read the guide ↗Go deeper with ProcXray
Inspect the process tree, resource history, and process details together. Start with the product overview or follow the setup guide.
Explore another topic
Memory pressure & leaks
A large memory number is only the beginning. Use memory pressure, app behavior, and changes over time to decide what deserves investigation.
5 guidesProcesses & background apps
Find what is running, identify its parent app, and inspect unfamiliar processes before deciding what to close. Compare built-in tools with deeper inspection workflows.
12 guides