PC Health Check: Four Numbers, Not Just One

You downloaded PC Health Check to find out whether the machine could take Windows 11, got your answer, and never opened it again.

It reports three other things while it is there, and two of them are numbers most people never see. One of those numbers is the single best predictor of how a laptop will feel in a year.

I read all four of the figures the app shows, directly rather than through it, and one of my readings came back as a zero that was simply wrong.

What the app is actually for

Broader than its reputation, and Microsoft says so in the first line.

⭐ Microsoft states the purpose on its PC Health Check page: it "brings you up to date info on your Windows device health, helping you take action to improve your device performance and troubleshoot performance problems".

⚡ The Windows 11 check is one section of four. Storage, battery and startup time are the others.

⚠️ Nobody markets those three to you, which is why the app has a reputation as a one question tool.

⛔ It is not part of Windows. Microsoft's own instruction if it is missing is to visit its download page and install it.

Is it even on your machine?

Ten seconds to check yours, and the answer here surprised me.

⭐ Microsoft says to search for it: "use Search on the taskbar to search for PC Health Check, then select it from the list of results."

⚡ It is not installed on this laptop at all, and this is a machine that has taken every update since May 2025.

⚠️ So it arrives by download rather than by Windows Update. Anyone who never went looking for it does not have it.

⛔ That also means an old copy can sit on a machine for years. Worth reinstalling rather than trusting a stale one.

It is not the only free Microsoft app that is missing from most machines. PC Manager arrives by download too, and mostly fronts things you already own.

The storage number

One of the three nobody talks about.

⚡ Microsoft describes it as showing "how much storage space is being used for your device's main drive, which contains your files, apps, and Windows".

⭐ This machine reads 453.6 GB total with 83.8 GB free. That is 81.5 percent used.

⚠️ Above about 90 percent is where Windows starts struggling for room to update and to page.

⛔ A full drive is a real cause of slowness. Sorted by how much you actually need to find.

The battery number, and the zero that was wrong

The reason to open the app at all, if you ask me.

⭐ Microsoft's wording: it gives info "on how your batteries are performing compared to their original capacity".

⚡ That comparison is the number that predicts the next year. Not the percentage on the taskbar.

⚠️ My first reading said this laptop had no battery. ⛔ It has one. I had asked the wrong Windows class, which returned nothing rather than an error.

⛔ Asked properly, it reports one battery, at 100 percent, with a full charge capacity of 35,032 mWh. The fuller reading is worth taking on its own.

The startup time number

Most likely of the four to make you change something.

⚡ Microsoft says it gives info "on the startup time for your device, along with more info about what affects these times".

⭐ This machine has been running for three days, so a fresh startup figure would mean waiting for a restart.

⚠️ Uptime is not startup time, and the app does not conflate them. Neither should you.

⛔ If yours is slow, the app names what is affecting it and stops there. The fixes are a longer story.

The Windows 11 check, which is the famous one

Still the reason most people open it, and now it has a deadline attached.

⭐ Microsoft says it "provides a comprehensive eligibility check for your device to ensure it meets the Windows 11 minimum system requirements", with info on why it is or is not eligible.

⚡ A machine already on Windows 11 does not need this section. It answers a question you have already passed.

⚠️ If it says not eligible, the reason matters more than the verdict. A switched off TPM is a settings change, and an unsupported processor is not.

⛔ That whole decision has its own page. Sorted by what your PC actually says.

Whether to install it at all

The answer depends on why you are asking, and the call is ours.

⚡ For the Windows 11 question alone, probably not. Settings already tells you whether the upgrade is offered.

⭐ For the battery figure, it is the friendliest route there is. The alternative is a command and a report file.

⚠️ Download it from Microsoft's own link and nowhere else. The name is copied by things that are not this app.

⛔ And if a search result offers you a health checker with a price, close it. Anything unfamiliar deserves a look before you run it.

Status: the four figures the app reports were read directly on 29 August 2026, on a Windows 11 Home 25H2 laptop, against Microsoft's own PC Health Check page. ⛔ The app itself is not installed here, so no screen of it is described, nothing was installed or changed, and no serial number, model or identifier is published.

What does the PC Health Check app do?

Microsoft describes it as bringing up to date information on your device health to help improve performance and troubleshoot problems. It has four parts: the Windows 11 eligibility check, storage, battery performance against original capacity, and startup time.

Is PC Health Check installed on Windows 11 by default?

No. It is a separate download. On this laptop, which has taken every update since May 2025, it is not present at all. Microsoft's instruction if it is missing is to download it from its own link and install it.

Is the PC Health Check battery report worth using?

It is the easiest route to the one battery number that matters, which is current capacity against the original. The alternative is running a report by command and opening the file. Both give the same answer and the app is friendlier about it.

Should I download PC Health Check to see if I can run Windows 11?

Probably not on its own. Windows Update already tells you whether the upgrade is offered to your machine, and if it is refused, the reason is what matters rather than the verdict. The app is more useful for the battery and storage figures.

The Short Version

• The app has four sections, not one. Only the Windows 11 check is famous.
• Microsoft describes it as reporting on overall device health.
• It is a separate download and is not on this laptop at all.
• Storage here reads 453.6 GB total, 83.8 GB free, 81.5 percent used.
• The battery figure compares current capacity against the original.
• My first battery reading returned zero because I asked the wrong class.
• Asked properly: one battery, 100 percent, 35,032 mWh full charge.
• Download it from Microsoft's own link. The name gets copied.

Where to Next

Search the taskbar for PC Health Check and see whether you even have it. Many people do not.

If the battery is why you are curious, that section alone justifies the download.

Read the storage figure while you are there, and treat anything above ninety percent as worth acting on.

Ignore the Windows 11 section if you are already running Windows 11, because it answers a settled question.

And if your battery figure differs wildly from what the taskbar percentage suggests, say both numbers in the comments. That gap is the interesting part.