How to keep an eye on your Mac's CPU from the menu bar

macOS does not put a live processor readout in the menu bar, so to keep an eye on your Mac’s CPU from there you need an app that adds one. Foreman does it with a live readout you can set to a graph with a percentage, a CPU and memory pair, or just an icon. Click the readout and a panel shows the apps using the most, with a button to end any of them.

Below: why a glanceable readout is useful, what macOS gives you without one, how to set up and read Foreman’s three styles, and what the panel contains.

Why a glanceable readout helps

Most slowdowns announce themselves late. By the time the fans spin up or the beach ball appears, the processor has been busy for a while. A readout in the menu bar lets you notice the start of the problem, when the cheapest fix is still available: closing one app.

It also answers a question you would otherwise have to open something to ask. Is the Mac slow because of something it is doing, or because of something else, like the network or a page that is loading slowly? If the readout is flat, the processor is not your problem, and you can stop hunting in the wrong place. If it is pinned high, you know to look.

A third use is learning what normal looks like for your Mac. Once you have glanced at it for a week, you know that it sits near the bottom when you read and hops up when you open a large project. Then a reading that is out of character stands out at once.

The caveat is that a high number is not automatically a problem. A processor at full tilt while a video exports is the Mac doing the job you gave it. What matters is high with no reason. If you want the longer version of that argument, high CPU usage on a Mac: what counts as high and what to do goes through it.

What macOS gives you without an app

Without installing anything, you have a few ways to look, and none of them puts a processor figure where you can glance at it.

• Terminal. Run top -o cpu and macOS prints a table of processes sorted by processor use, refreshed each second, with machine-wide figures above it. It counts each core as 100 percent, so one busy app can read above 100. Press q to leave. It is accurate, but it is a window you have to open and read.
• Force Quit window. Option-Command-Escape lists the open apps, and shows when one is not responding. It shows no figures.
• The battery menu. On a laptop, click the battery icon in the menu bar. Under “Using Significant Energy” it names apps drawing a lot of power right now, a rough pointer to who is keeping the processor busy. It shows names, not figures.

None of these gives you a number at a glance. That is the gap a menu bar readout fills.

Set up Foreman’s menu bar readout

Foreman is a Task Manager for macOS by Everyday Mac Tools. Open it with Control-Shift-Escape, or click the readout and choose “Open Foreman” in the panel. The readout is controlled from Foreman’s Settings, which has its own window. Three settings matter here:

• “Show Foreman in the menu bar” puts the readout in the menu bar.
• The menu bar style picks one of three readouts, described below.
• Refresh speed sets how often the figures update: “Twice a Second”, “Every Second”, “Every 4 Seconds” or “Paused”.

If you close the window, Foreman keeps running in the menu bar and on Control-Shift-Escape, and it leaves the Dock. That is the “Keep Foreman running” setting, and the first time you close the window it explains this once. With the window closed, Foreman reads a few machine-wide counters for the menu bar. You can also set “Open at login”, so the readout is there after a restart without you doing anything.

The three styles

CPU graph and percentage. A live graph of the processor with its percentage. A graph shows the recent past as well as the moment, so you can tell a brief spike from a steady climb. This is the one to pick if CPU is the thing you want to watch.

CPU and memory. The processor and memory together. This is the better pick if you suspect memory, because the processor and memory together tell you more than either alone. A Mac with an idle processor that still feels slow is often short of memory, and this style keeps both in view. For memory pressure itself, open the Performance page.

Icon only. No figures, just Foreman’s icon. It is the quietest option, for people who want Control-Shift-Escape and the panel on hand but do not want any movement in the menu bar. It will not tell you anything by itself.

One practical note on the menu bar: macOS hides menu bar items that do not fit, which happens on a crowded menu bar, especially on a MacBook with a notch. If you cannot see the readout, try a narrower style or quit another menu bar app.

Which to choose? Try the graph first. A moving graph is easier to notice out of the corner of your eye than a number that changes, and you can always switch in a few seconds.

What the panel shows

Click the readout and a panel opens. It has:

• CPU, Memory, Disk, Network and GPU, each with a live graph.
• Using the most, a list you can switch between CPU and Memory. It names the apps using the most, and each has an End Task button.
• Open Foreman, which opens the full window.

The list is the useful part. You see a spike in the readout, click it, and the name at the top of the list is usually the answer. End Task asks the app to quit the way Command-Q does, so it can offer to save your work. Press it again within a minute to force quit. An app that macOS has marked as not responding is force quit at once. Force Quit on an app with windows asks first, because you lose any unsaved changes.

Parts of macOS appear in the list too, and some should be left alone. Foreman never offers to end kernel_task or launchd, and it warns before ending something like WindowServer or loginwindow, because it would log you out. If a macOS process is at the top for a while, read its plain-English name, and wait for it. What is kernel_task on a Mac and why does it use so much CPU is a good example, because a high figure there often means the Mac is slowing itself down to stay cool.

If an app should stay open but is eating the processor in the background, use Efficiency Mode instead of ending it: in the background it runs at background priority and is held to about a quarter of the processor time it would take, in short bursts, and in front it runs at full speed.

What it does not do

It does not send you alerts, so nothing tells you when the figure crosses a line. It does not show temperatures or fan speeds, and it does not keep a history of an app after it quits. It is a live view for you to glance at, and for the rest you open the Performance page, which shows a minute of history.

Foreman costs $12 once for up to 3 Macs, and it is free for 24 hours, so you can put the readout in your menu bar and see whether you glance at it.