How to test storage speed without installing apps

Your computer takes a long time to open files, or you want to check a new drive without installing benchmark software. A browser test can give you a quick read on storage performance, but the result depends on more than the drive alone.

The Storage Test measures large-file speed and small writes, then gives a score out of 100. Use it to compare results under similar conditions, not as a complete diagnosis of your storage device.

Run a storage speed test

1. Open the Storage Test in the browser on the computer you want to check.
2. If the browser asks to use storage for the test, allow it. Browser storage permission controls whether a page can save test data for its work. See what browser storage permissions mean for a disk test.
3. Close large downloads, file copies, game updates, and other demanding tasks. If you are testing a laptop, connect its charger.
4. Run the test and note the large-file read and write speeds, the small-write result, and the score.
5. For a useful comparison, run it again with the same browser and similar conditions. Avoid comparing one result taken during a file copy with another taken while the computer is idle.

The test runs in your browser, so there is no benchmark app to install. The browser may not let you choose a particular physical drive or tell you exactly which drive backs its storage. If your computer has several drives, treat the result as a check of the storage the browser can access, not a guaranteed measurement of every drive.

What the result means

Large-file speeds are higher than small-write speeds

This is common. Moving one large file is different from saving many small pieces of data. Small writes can take longer because each operation has overhead, and the drive or operating system may handle them differently. A difference alone does not mean the drive is damaged. For more detail, see how to interpret storage test read and write speeds.

The read and write speeds look low

The test has measured slower performance in this browser and set of conditions. Background activity, a nearly full drive, power-saving behavior, or a slow connection between an external drive and the computer can all affect what you see. A browser test is not the same as copying a file in your usual apps, so compare results from the same test rather than treating the number as a universal drive rating.

The score is lower than you expected

The score is a summary from this test, not a grade assigned by your computer manufacturer. It does not prove that a drive is healthy or faulty. Compare it with a repeat run on the same computer, and look at the individual read and write results as well as the score.

Results change a lot between runs

Another task may be using the drive, the laptop may have changed its power behavior, or the browser may be handling its storage differently. Close background work and repeat the test once. A single inconsistent run is not enough to identify a hardware problem.

How to get a more reliable result

1. Stop other storage activity. Pause file transfers, cloud sync, downloads, game updates, and video exports before testing. On Windows 11, open Task Manager with Ctrl + Shift + Esc to see whether an app is using substantial resources. On macOS, open Applications › Utilities › Activity Monitor.
2. Connect a laptop to power. Battery-saving behavior can change performance. On Windows 11, check Settings › System › Power & battery › Power mode. On a Mac laptop, check System Settings › Battery and compare while connected to power.
3. Check available space. Very low free space can make normal computer use harder and can affect some storage operations. In Windows 11, open Settings › System › Storage. On macOS, open System Settings › General › Storage. Free space if the drive is nearly full, then test again.
4. Restart and repeat the test. A restart can stop a stuck process or pending task from competing with the test. After the computer starts, open the same browser and test before launching other demanding apps.
5. Check the external connection. If you are testing an external drive, connect it directly to the computer rather than through a hub, and try another port or cable. Some cables and adapters support charging but provide slower data transfer.

When the drive may be failing

A low score by itself is not evidence that a drive is failing. Take it more seriously if the drive also disappears, produces repeated read or write errors, freezes the computer during ordinary file access, or makes files unavailable. Back up important files as soon as you can. Do not keep running repeated speed tests on a drive that is making unusual noises or losing access to data.

If the problem follows an external drive to another computer and cable, contact the seller or manufacturer if it is under warranty. For an internal drive, use the computer maker's support or a repair shop to check it. Replace a drive that repeatedly fails normal reads or writes, and keep a separate backup of important files.

What a browser test cannot tell you

A browser test does not give a complete picture of drive health, exact hardware specifications, or every kind of storage workload. It cannot confirm that a drive will stay fast during hours of sustained transfers, and its score is not a substitute for copying the same real files you use every day. Use it as a quick comparison, then check normal file behavior and back up anything important.