Should You Defrag an SSD?

If you’ve ever owned a traditional hard drive, you have probably defragged it at some point along the way. This is because defragging a hard drive is necessary due to the way it is built. In recent years, many people have been replacing their HDD with an SSD due to the impressive technology and additional benefits. Those who are used to defragging their hard drives may wonder if it is necessary to defrag an SSD. We answer that question below.


Should I defrag my SSD?

The short answer is this: you don't have to defrag an SSD.

To understand why, we first need to look at the purpose of defragmenting a drive. Defragging ensures that large files are stored in one continuous area of a hard disk drive so that the file can be read in one go. Mechanical drives have a relatively long seek time of approximately 15ms, so every time a file is fragmented you lose 15ms finding the next one. This really adds up when reading lots of different files split into lots of different fragments.

However, this isn't an issue with SSDs because the seek time are about 0.1ms. You won’t really notice the benefit of defragged files — which means there is no performance advantage to defragging an SSD.

SSDs move data that's already on your disk to other places on your disk, often sticking it at a temporary position first. That's what gives defragmenting a disadvantage for SSD users. You’re writing data you already have, which uses up some of the NAND's limited rewrite capability. So, you get no performance advantage whatsoever, but you are using up some of the limited rewrite capability.

To summarize, do not defrag an SSD

The answer is short and simple — do not defrag a solid state drive. At best it won't do anything, at worst it does nothing for your performance and you will use up write cycles. If you have done it a few times, it isn't going to cause you much trouble or harm your SSD. You just don’t want this to be a scheduled, weekly type thing that takes away from the finite number of SSD rewrites. There are other ways to clean up and increase speed on your computer. There are even reasons for formatting an SSD, encrypting SSDs, and ways to increase storage space on a SSD. They all serve a purpose — there just isn’t a reason to defrag an SSD.

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