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We all use Preview quite often on our Mac. Whether it’s to open a PDF or an image, you need to use Preview, as it’s the default app. Sure, you can install third party apps if you want. But realistically, most people will use the default app. And the problem with default apps is that they aren’t the best when it comes to optimisation

A lot of the time, people complain about Preview being slow and not working the way you want. What makes it slow down and how can you tackle this Preview on Mac issue? Thankfully, there are a few methods to help you solve the issue!

What causes Preview to be slow on your Mac?

  • This has to do with some applications that are resource-heavy, and Preview is left out of resources. In that case, it will slow down quite a lot.

  • Continually opening stuff will increase the cache size for Preview. And when that happens, too much cache will end up becoming an issue.

  • Maybe the file you want to open is corrupted. Sometimes, the issue is not with Preview itself, it may very well have to do with the file that you are trying to open.

What should you do when the Preview app is very slow?

Update your apps and system

Sometimes, all you have to do is to perform a software update or an OS update. That’s very helpful, and it certainly helps speed things up quite a bit. What’s very important is that you update your system often, as it will help immensely.

Start using a Mac cleanup tool

The role of such a tool is to help remove the clutter from your device. You can remove cache, temporary files and all kinds of duplicate files, among many others. The truth is that cleaning up the system and removing stuff that wouldn’t be used anyway is incredibly helpful. It allows you to offer more resources to the apps you want to use, including Preview.

Close resource-heavy apps

You can enter the Activity Monitor and in there you can check the CPU and memory consumption. Close those apps that consume the most memory and CPU, then it will be easier to allocate more of that to Preview and other apps that you actively want to use. Plus, the last thing you want is to have a lot of apps that you’re not using running in the background for no reason.

Adjusting and figuring out what works well and what stuff you can improve is always going to be very helpful and quite effective. Some apps might be very resource-heavy, others might not require a lot of stuff at all. But you never know what apps can be demanding, even Preview might need a lot of CPU and memory when it deals with very complex files.

Delete cache files manually

It’s possible to find these cache files in the Library/Caches folder. You want to try and remove cached content from there, as it will speed up the process. As we mentioned earlier, using a Mac cleanup tool is actually the better option to consider. But it won’t always work, and that’s why we encourage you to manually delete the cache, if you can.

Is it a good idea to remove cache manually? Yes, but you need to do that often. Removing cached files is going to improve your overall Mac performance, so it makes a lot of sense to do it. And the best part is that it will improve how many apps work, including Preview, but also a variety of other tools as well.

Re-save your files

Sometimes, there can be an issue with Preview, and restarting the Mac will normally help take care of the problem. But you can also select File/Export and then save the PDF file under a new name. It’s effective, it will provide you with a great experience, and in the end, the outcome as a whole is nothing short of impressive.

Remember, saving your files again means you can have a backup. But it also means that any problems you had with the previous file might very well be sorted out. It always comes in handy to save your files once again, because you never know what causes the Preview problem.

Conclusion

It’s very helpful to learn all these tips and tricks to help you speed up Preview as much as possible. Sure, it can be rather slow at times, and that’s exactly the thing you need to think about. What really matters is the Mac performance and your overall user experience. Using these tips and ideas can offer you a good insight into what you can do to speed things up and ensure that Preview, but also other apps run properly!

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