Track Safari Web Content RAM and CPU in Activity Monitor

This article provides a step-by-step guide on how to track the exact CPU and RAM usage of individual Safari Web Content processes using the macOS Activity Monitor. By configuring Activity Monitor to display processes hierarchically, you can easily isolate specific websites and open tabs to see the precise system resources they consume in real time.

1. Open Activity Monitor

Press Command + Space on your keyboard to open Spotlight Search, type Activity Monitor, and press Return. Alternatively, open Finder, navigate to the Applications folder, open the Utilities folder, and double-click Activity Monitor.

2. Enable Hierarchical View

By default, Safari Web Content processes are scattered throughout the process list. Grouping them under the main Safari application makes tracking individual tabs much easier.

  1. Click View in the top menu bar of your screen.
  2. Select All Processes, Hierarchically.
  3. Locate Safari in the process list and click the arrow to the left of the application icon to expand it.
  4. If you see a sub-process named Safari Networking or Safari Web Content, expand those as well. Each open website will now be listed directly beneath the main Safari process, labeled by its specific domain name (for example, apple.com or google.com).

3. Monitor the CPU Footprint

To see how much processing power each individual Safari tab is using:

  1. Click the CPU tab at the top of the Activity Monitor window.
  2. Find your expanded Safari process list.
  3. Look at the % CPU column next to each domain name. This number represents the real-time percentage of your Mac's processor capacity that the specific webpage is actively using.
  4. Check the CPU Time column to see the cumulative amount of time the processor has spent actively running code for that specific tab since it was first opened.
  5. Click the % CPU column header to sort the processes, bringing the most demanding tabs inside the Safari group to the top of its sub-list.

4. Monitor the RAM Footprint

To view the exact amount of system memory each webpage is consuming:

  1. Click the Memory tab at the top of the Activity Monitor window.
  2. Locate the expanded Safari process list.
  3. Look at the Memory column. This displays the exact amount of RAM (in megabytes or gigabytes) currently allocated to each individual website process.
  4. Look at the Compressed column to see how much of that specific tab's memory macOS has compressed to free up active RAM for other tasks. If this column is not visible, right-click any column header and check Compressed to enable it.
  5. Click the Memory column header to sort the list and instantly see which website is using the largest amount of RAM under the Safari umbrella.

5. Terminate Resource-Heavy Tabs

If you find a specific Safari Web Content process using an excessive amount of CPU or RAM, you can close that single tab directly from Activity Monitor without shutting down the entire browser.

  1. Click on the problematic website process under the Safari list to highlight it.
  2. Click the Stop button (an octagon with an "X" inside) at the top of the Activity Monitor window.
  3. Select Quit or Force Quit.

The specific tab in Safari will immediately unload and display a message stating that a problem occurred with the webpage. This instantly frees up the RAM and CPU resources it was holding while leaving the rest of your open Safari tabs untouched.