Safari Running Slow on Mac? 10 Fixes

Safari is the browser most likely to be blamed for a slow Mac and least likely to deserve it. Nine times out of ten the problem is one extension, one heavy page, or a pile of stored website data — not the browser. There's a thirty-second test that tells you which, so start there rather than working down a list.

The thirty-second test

Open a private window (File → New Private Window) and load the page that's slow. Private windows run without extensions and without most stored site data.

• Fast in private, slow normally → it's an extension or your stored website data. Go to fixes 1 and 2.
• Slow in both → it's the page itself, your connection, or the Mac. Skip to fix 5 onwards.

1. Audit extensions

Extensions run inside every page you load, so a single badly written one slows the whole browser.

1. Open Safari → Settings → Extensions.
2. Untick every extension. Confirm Safari is fast again.
3. Re-enable them one at a time, browsing normally for a few minutes between each.
4. Uninstall the one that brings the slowness back — and anything you re-enabled out of habit but never actually use.

2. Clear website data

Years of cookies, local storage and databases from thousands of sites add up, and a corrupt entry can make one site crawl indefinitely.

Safari → Settings → Privacy → Manage Website Data → Remove All. This signs you out of most sites, so have your passwords to hand. To clear one site only, search for it in that list and remove just that entry — the surgical option when a single site misbehaves. The full walkthrough.

3. Empty the cache without clearing everything

The Develop menu has a cache-only option that leaves your logins alone. Enable it in Safari → Settings → Advanced — the checkbox is Show features for web developers on macOS 14 Sonoma and later, and Show Develop menu in menu bar on macOS 13 Ventura. Then use Develop → Empty Caches.

4. Deal with the tabs

Tab count matters less than tab weight. Ten news articles cost almost nothing; a document editor, a project board and a video call together can cost gigabytes. Safari unloads inactive tabs on its own, but a heavy tab you keep returning to never gets unloaded.

Open Activity Monitor, sort the Memory tab, and look at the Safari Web Content processes — hovering over one shows which page it belongs to. Close the expensive ones, or move them into a Tab Group you open only when needed. If tabs from your other devices are also loading, that's more to reconcile at launch.

5. Check whether it's actually the network

Pages that take a long time to start loading, then render instantly, are a network symptom, not a browser one. Test the connection and flush the DNS cache — stale DNS is a classic cause of a browser that seems to hang before every page.

6. Turn off search suggestions if typing is laggy

If the delay is in the address bar rather than the page, Safari is querying a suggestion service on every keystroke. Safari → Settings → Search — untick Include Safari Suggestions and Include Search Engine Suggestions. You lose the dropdown; typing becomes instant. Related: turning off Spotlight's web results.

7. Look at the start page

Safari's start page can show Favourites, Frequently Visited, Reading List, iCloud Tabs, Siri Suggestions and a background image — and it renders all of it every time you open a tab. Click the settings button at the bottom-right of the start page and turn off the sections you don't read. If new tabs are the slow part, this is usually why.

8. Give the Mac room

Safari is a heavy app, and it suffers first when the system is short of resources. If memory pressure is yellow or red, or the startup disk is nearly full, Safari will be slow no matter what you change inside it. Check memory pressure and free disk space before blaming the browser.

9. Update macOS

Safari ships as part of macOS, so there's no separate Safari update — System Settings → General → Software Update is how you get browser fixes. Point releases regularly include real rendering and memory improvements. From Terminal, the softwareupdate command does the same.

10. Start clean with a second profile

On macOS 14 Sonoma and later, Safari supports profiles — separate sets of extensions, history and cookies. Create one in Safari → Settings → Profiles and use it for a day. If the new profile is fast, the problem is accumulated state in the old one, and you've isolated it without losing anything. On macOS 13 Ventura, the equivalent test is a fresh macOS user account.

The settings-level fixes above are one-click, reversible toggles in Mainspring — labelled in plain English, with an undo button for every one.

Common questions

Why is Safari slower than Chrome on my Mac?

Usually it is not, on the same pages. Safari is generally lighter on memory and battery on Mac hardware. A Safari that feels slower is normally carrying extensions or years of website data that a freshly installed Chrome is not.

Does clearing website data in Safari delete my passwords?

No. Passwords are stored in Keychain, not in website data. Removing website data does sign you out of most sites, since it deletes cookies, so you will need to log in again.

How many tabs can Safari handle?

There is no fixed limit, and weight matters more than count. Dozens of article pages are cheap; a handful of document editors, dashboards or video calls can consume gigabytes and slow everything down.

How do I update Safari on a Mac?

Safari updates arrive with macOS updates. Open System Settings, General, Software Update and install what is offered; there is no separate Safari installer.

Why is typing in the Safari address bar laggy?

Safari queries suggestion services on each keystroke. Turning off Safari Suggestions and search engine suggestions under Safari Settings, Search removes the delay at the cost of the dropdown.