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Performance

How to Speed Up a Slow Mac: The Complete Guide

March 2026·6 min read

Macs are designed to run efficiently for years — but they do slow down, and usually for fixable reasons. Here is how to diagnose and fix a slow Mac without a trip to the Apple Store.

Check Activity Monitor first

Open Activity Monitor in Applications > Utilities and click the CPU tab. Sort by CPU usage to see what is consuming the most processing power. Sort by Memory to see what is eating your RAM. This tells you immediately whether the problem is a specific app or a system-wide issue.

Free up storage space

macOS needs breathing room. If your drive is more than 85% full, performance degrades noticeably. Go to Apple menu > About This Mac > Storage to see what is using space. The Optimise Storage option can automatically move old files to iCloud if you are running low.

Manage login items

Go to System Settings > General > Login Items to see everything that launches at startup. Remove anything you do not use daily. Common offenders include old applications that install helper tools, music software, and developer tools you no longer need.

Check for software updates

Apple regularly releases performance improvements in macOS updates. Go to System Settings > General > Software Update and install anything pending. Outdated system software is a common cause of slowdowns, particularly after a major macOS version upgrade.

Consider a RAM or storage upgrade

If your Mac has 8GB of RAM and you regularly use multiple applications, upgrading to 16GB makes a significant difference. If you still have a spinning hard drive, replacing it with an SSD is the single biggest performance improvement you can make — typically three to five times faster at everyday tasks.

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