Let’s be clear about something prior to diving in: managing, editing, and processing tens or hundreds of images at a time is never going to be a lightning-fast process. That said, an average Mac user will inevitably notice Adobe Lightroom running slow from time to time.

Although a quick restart can sometimes be enough to get things back to normal, it’s likely that whatever process was responsible for making Lightroom slow will manifest again soon enough. Fortunately, there are a number of things you can do to consistently speed up Lightroom.

The really good news is that most of the tips presented here aren’t all that technically demanding, so they’re easy enough for anyone to try. May you never have to wait around for Lightroom to export a huge batch of photos again!

How to speed up Lightroom on your MacBook

Before you can speed up Lightroom, you need to get to the root of why Lightroom is running slow on your Mac. In most cases, the reason behind poor performance falls under one of three categories:

  1. Insufficient Camera Raw cache size
  2. Software issues, including the way you use Lightroom
  3. Hardware problems

Good news is all of these could be solved, albeit with various degrees of difficulty.

    1. Increase the default cache size

    The easiest and one of the most productive fixes you can do is upping the cache size: while the default cache size set by Lightroom ranges from 4 to 10 GB, many users see improvements by increasing this to somewhere between 50 and 70 GB. It goes without saying that the more photos you’re working with, the larger cache size you’ll need. 

    It might seem surprising that Adobe sets such a (comparatively) low cache size, given that the average Lightroom user is likely to be working with thousands, tens of thousands, or even more images, but luckily this problem is very easy to fix.

    2. Accelerate Lightroom with proper settings

    If changing your cache size doesn’t help to speed up Lightroom, there are a few other things you can do with the app itself to reduce slowdown. A large number of presets, for example, can cause sluggish performance and (while you’d need a very large number to see any negative impact) clearing them out can help to improve how the app runs.

    Additionally, actions like rendering 1:1 previews often take a long time to create because they involve the processing of so much data. Standard previews will usually do the job just as well, unless the work you’re doing is only minuscule in scale. When you really need 1:1 previews, setting aside time to leave your computer alone and render them manually is often the most effective solution.

    Counterintuitively, hanging on to 1:1 previews rather than discarding them can actually improve performance in the long run: when you discard 1:1 previews Lightroom has to recreate new ones if you need them again, even if only for very minor revisions.

    Thinking critically about the way you apply adjustments might also help to speed up Lightroom. Local corrections and Spot Removal, for example, aren’t designed for use on a large number of corrections per image. Adobe even recommends that you use Photoshop for this level of correction. If you’re dead set on using Lightroom to make such changes, clearing out your History panel can have significant impact as it doesn’t delete its content automatically unless instructed to do so.

    3. Upgrade to latest software and macOS

    Basic as it may be, it’s always worth following tried-and-tested advice about making sure you’re using the most recent version of Lightroom. If you’re running Lightroom CC then that won’t be an issue but, for those still making edits with an older version of Lightroom CS, it may be time to upgrade. 

    Similarly, upgrading to the latest version of macOS is advised when you’re trying to get the most out of Lightroom. While it’s unlikely that changes like these will result in any huge improvements to Lightroom’s performance, it’s true that newer versioning typically addresses incompatibility issues and bugs, even if it may introduce a few new ones of its own.

    System Preferences - Software Update

    4. Switch to automatic Mac maintenance

    You probably knew it was coming, but it’s time to look at one of the most significant ways to speed up Lightroom: slow performance is often down to insufficient RAM and hard disk space. Upgrading your setup is an option if your machine is totally outdated, and can be worth it if it significantly improves your efficiency by reducing the amount of time you spend waiting around.

    However, and this should come as good news for the cash-strapped, it’s not the only option! An app like CleanMyMac X, as the name suggests, is a great way of clearing some hard disk space and removing other unnecessary and outdated files clogging up your Mac and resulting in Lightroom running slow.

    Using CleanMyMac X is simple:

    1. Download CleanMyMac X app for free and launch it
    2. Proceed to perform a Smart Scan to streamline your system overall
    3. Go through additional scans like Optimization and Mail Attachments to completely rid your Mac of waste

    Upgrading your machine should really be at the very end of your to-do list, since most of the tips above will have a noticeable impact immediately. If you still find yourself asking, “why is Lightroom so slow?” on a regular basis, then you’ll want to keep an eye on the amount of disk space and memory available.

    Most of us, especially photographers hanging on to all those shots from years ago “just in case,” operate with less disk space and RAM than we perhaps should be. If you’re not up for the mammoth task of sorting through all your files manually, an app like CleanMyMac X is a great option for automating the process and purging duplicate files, outdated caches, and hidden content you no longer require with the push of a button.