TrimCheck : Find if TRIM is Working for SSD in Windows

When you delete a file in Windows, the operating system just marks that file as unavailable in the file system and all the storage space occupied by it as available for further data writing, even though all the file data is still present. This is why those file recovery program can recover your deleted files easily – they can just read the deleted file data back and save it somewhere else. But this makes all the difference between how things work in a hard disk drive (HDD) and a solid state drive (SSD).

An HDD can just overwrite the contents of the space that was occupied previously by a deleted file whenever it needs to write new files. But an SSD cannot do this – it first has to wipe the entire block of memory where the file was stored and only then write the new data. This makes the data writing slower on SSD compared to HDD. A workaround is to enable the TRIM command for SSD. The TRIM command automatically wipes the blocks and fills it with zeroes as soon as a file is deleted, so that the next time when it has to write new files, it takes very less time.

In order to check whether TRIM is working for the SSD’s in your Windows PC, you can use the TrimCheck tool. It does not check the settings in Windows to find this out. It actually carries out tests on your SSD’s to see if the TRIM command is really working or not.


Using TrimCheck tool is very easy. All you have to do is put the downloaded EXE on the same drive somewhere that you wish to test. The first time you run it, it generates a file trimcheck-cont.json in the same folder as the EXE file. It may tell you to turn on TRIM if it is not already enabled in your Windows PC. In order to enable TRIM, you can give the following command in an elevated command prompt:

fsutil behavior set DisableDeleteNotify 0

After this launch TrimCheck once again and it will perform the tests to tell if you if TRIM is working. Basically, it creates a file on your SSD, fills it with random data, then deletes it and then checks if the data in the location where the file was stored has modified or not. If the data has been modified then TRIM is working.

You can download TrimCheck from