hardware upgrade on iMac 18,1

Both RAM and SSD supposedly can be upgraded; however, professional installation is definitely recommended as it is not for the faint of heart, so you will need to find an authorized service provider. However, Apple does not consider it user upgradeable and may refuse to work on any repair problem later.

And no, I would not recommend getting any RAM except from the two recommended RAM vendors: either OWC (macsales.com) or Crucial direct. And no, you will need to stick with the exact specs RAM.

https://eshop.macsales.com/shop/memory/imac-2017-21.5-inch

While you're checking that out, take a look at the install videos on their site.

An easier way would be to get an external SSD in an enclosure, clone your entire system to it and then use that as a boot drive. The 21.5" default 5400 rpm drive is notoriously slow; I just bought a 21.5", but bought one with an SSD and more RAM.

What rkaufmann87 said. Start by uninstalling Clean My Mac. It is scamware that at best doesn't do anything new and at worst causes exciting new problems when running a 'fix'. For example, all of the system information you posted can be natively viewed with Apple's Activity Monitor (Applications -> Utilities -> Activity Monitor), and 'freeing' memory just purges cached files which then slows the system down as it reloads the files it thinks it still needs.

I'd suggest starting by reinstalling or cloning MacOS onto an external USB 3.1 SSD. That will directly solve the disk speed issues and indirectly alleviate memory issues by providing fast swap space for virtual memory. Otherwise, what babowa said.

This is part of the problem: "entry level" probably for education or very light use.

 Model Identifier: iMac18,1

 Processor Name: Intel Core i5

 >>>>Processor Speed: 2.3 GHz

 Number of Processors: 1

 >>>>Total Number of Cores: 2

The next model up that year (US$200 difference) started with a 3.0ghz quad-core processor. Geekbench scores on the MacTracker database show the next model up at almost 50% faster for about a 20% increase in cost:

However, the external solid-state drive option others have mentioned will make a noticeable improvement in how fast the computer starts up and loads apps, the two things where people most complain about slowness. Remember the drive enclosure must be USB 3.0 or faster and the SSD inside must be rated at SATA 6GBps to get maximum benefit.

The change that Mike Sombrio mentions in how the Mac OS handles RAM happened with OS 10.9 "Mavericks" (in 2012). The new metrics for judging Mac RAM condition are both shown in Activity Monitor > Memory tab, and are "Memory Pressure" and Swap Used." Pressure should be in the green and swap used at or near zero.

As Mike wisely advises, "Memory Used" is no longer the indicator many people think it is. That is pre-2012 thinking.

Please uninstall Clean My Mac, it is malware! Download EtreCheck and run its report and then please post it. Mac OS should never have third party antivirus, cleaning or any other third party “maintenance” apps installed. The most effective security app for Mac OS is Mac OS itself, simply keep it up to date. Adding cleaning, AV apps will only make Mac OS slow, unstable and appear buggy.

I wholeheartedly agree with the above advice. Regarding ram utilization, you WANT all of your ram to be used. Unused resources are wasted resources. Mac OS will use all it can and properly allocate ram where it's needed, and it does an exceptional job with it. You NEVER want to use a third party app that claims to speed up, clean up, tune up or optimize a Mac, they will without exception do the opposite as they interfere with Mac OS. When dealing with a Mac you want to forget everything you ever learned about windows.

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