Windows 11 Task Manager Update 24H2 Refines CPU Usage Calculation for Accurate Performance Metrics

With the release of the Windows 11 24H2 update KB5058411, Microsoft has adjusted the formula for CPU usage to align with the metrics shown in the «Performance» and «Users» tabs. This feature previously calculated metrics for the «Processes» tab in the Task Manager. The data was previously computed using a different formula, which sometimes led to discrepancies in the metrics.

As a result, even seasoned users relying on the Task Manager to assess performance could struggle to pinpoint issues. For instance, any process in the «Processes» tab could individually display a usage of up to 100%, but adding these figures together was not particularly meaningful.

This confusion stemmed from the default use of the Processor Utility metric, which measures the «utility» of the CPU. In contrast, the «Performance» and «Users» tabs employed a more accurate method that compares the percentage of CPU time used to the Processor Utility figure, aligning with industry standards. The same formula is utilized by third-party tools and applications from OEM manufacturers to calculate CPU load.

In the previous version, the «Processes» tab did not account for the number of CPU cores. Hence, when even a single core on a 16-core chip was fully utilized, the CPU was reported as running at 100%.

Another drawback was the outdated calculation method, which was based on the CPU’s base clock frequency. Cores operating in turbo mode could report values exceeding 100%, which were then capped at 100% in the display.

Now, all tabs in the Task Manager utilize the formula: «CPU usage percentage = CPU time allocated to the tasks of this process ÷ (total elapsed time × total number of available logical processors in the system).» For example, if the overall CPU load is 69%, summing up the loads of individual processes will yield consistent results.

To revert to the original calculation method, users can navigate to the «Details» tab, right-click on the column header, and select Processor Utility from the list of options.

The Task Manager update has aligned it with Windows Management Instrumentation (WMI) classes, which are utilized by tools such as Perfmon (Performance Monitor), PowerShell’s Get-Counter, and various third-party performance monitoring solutions.