How to Speed up High Sierra

Faster startup

Unneeded apps loading on login will stretch out startup and slow your Mac. Open System Preferences > Users & Groups > Login Items, click any app you don’t need every time, and click the minus button to stop it loading on login.

Limit iCloud

Especially if you have a poor internet connection, backing up to iCloud will slow everything down. If signing out is too extreme, consider opening System Prefs > iCloud > iCloud Drive and turning off Desktop and Documents syncing.

Disable encryption

It’s less of an issue on Macs with SSDs, but with a conventional hard disk, there can be a lag as FileVault encrypts or decrypts your files. If you don’t need its data security, you can disable it in System Preferences > Security & Privacy.

Eliminate eye candy

If running High Sierra on an older Mac, you can speed up everyday use by disabling unnecessary eye candy such as Finder’s visual effects. Reduce motion and disable transparency in System Preferences > Accessibility > Display.

Strip back Spotlight

After any macOS update, Spotlight re-indexes your drives, so things may seem slow afterwards. Leave your Mac on, so Spotlight can carry on when it’s idle; filter Spotlight’s searching in System Preferences > Spotlight.

Browse more simply

The more tabs you have open, the more of a drain your browser is. Plus, a surprising number of slowdowns are caused by buggy website scripts or runaway client-side processes. Quit your browser when you don’t need it.

One browser only

Browsers differ — for example, we find Chrome plays better with some web apps than Safari — but browsers are also very demanding on your CPU. Don’t keep one running in the background when you’re using another.

Repel hijacks

Safari can be the victim of browser hijacks, which can infest your Mac with unwanted adware and other irritations. The shareware DetectX ( sqwarq.com/detectx) does a fine job of finding these, so you can trash them.

Update your apps

High Sierra makes some low-level changes to how things operate, and some older apps may not play well with this. If an app freezes on startup or quits for no obvious reason, check Software Update or the developer’s website for updates.

Clear out the trash

High Sierra uses disk space for memory swapping, but if your drive has less than 10% free, that often has a big drag on performance. Empty that trash, declutter Documents, and archive stuff you’re not using to an external drive.

Spring clean

We’re big fans of housekeeping app OnyX ( titanium-software.fr). It sorts small things, such as cache files, that can collectively have a big impact — but make sure you use the right version for the version of macOS you’re running.

Start from scratch

Ensure you have a reliable, up-to-date backup. Erase your drive, reinstall High Sierra, and restore your files from your backup. This should cull any corrupted prefs and defragment your data, speeding up non-SSD drives.