We frequently recommend our users to clear cache if their site doesn’t serve the actual optimized images. Here is a short guide for flushing your cache. Find what cache is, when you need to purge it, and how to do this in the most common situations.
The cache solutions are pretty smart nowadays and they know when your files are modified. Except when they don’t :-). Every piece of software has glitches from time to time, and it’s good to know how to manually clean your cache so your WordPress site looks like it’s supposed to.
What is cache in simple words?
Websites, browsers or your hosting provider can temporarily store data in order to serve it faster to the visitors.
This temporary memory is called cache and is tremendously useful.
Most of the sites are dynamic = their pages are built on the fly by diverse scripts that put together information, images, and texts in a structured way. What you usually see when you open a webpage is assembled for you in just that moment.
This is not an issue for a site with few visitors. But when hundreds of readers access your web pages at the same time, your server has to serve the same media content again and again for each one of these visitors, while the necessary scripts make thousands of database requests in the background.
Finally, your site slows down or crashes.
This is where the cache solutions come in handy to help your WordPress site serve recently used resources from the temporary memory. Basically, a webpage previously generated for a visitor will be displayed for the next visitors.
Tip: Most of the WordPress sites are small and have cheap hosting packages. Cache is especially important for these sites because any traffic spike could spend their limited resources.
If cache is such a good thing, why do I need to delete it?
Because sometimes these solutions don’t realize that you updated your WordPress site or that some plugins made some changes. You refresh your page, and nothing happens. The usual suspect for this behavior is the cache memory which continues to serve the old content.
So, flush your cache if:
– You updated your site, but nothing has changed.
– You optimized your images with a web hosting plugin, but the old uncompressed images are still there.
The easiest way to check if you have a cache issue
Let’s say that you have ShortPixel plugin or other image optimization plugin installed on your site, and even if you optimized your images, they seem to have the same size as the originals. Most likely, you have a cache issue, and you can easily verify that.
Tip: Add ?something at the end of the image URL and click Enter key. This will force your server to return the actual image.
This simple verification works in most cases and it takes only a few seconds.
You could also check the actual size of your images using a FTP software.
WordPress sites – types of cache:
When you have a WordPress site, there are four types of cache you need to know about:
Browser cache: All modern browsers store images and information in their cache memory.
WordPress cache plugins: These plugins do the job at the site level. Basically, they help you to implement the best practices regarding the cache.
Hosting cache: Hosting providers mission is to cleverly distribute resources, and serving webpages from the temporary memory is one of the best ways to accomplish this.
CDN cache: CDN (Content Delivery Network) services provide you with servers located all over the world that allow your site to load faster for all your users no matter where they live. Like your hosting company, the CDNs could serve your site from cache memory.
How to delete browser cache in Firefox, Chrome, Opera and Edge. Quick and fast!
By default, browsers store the media files and information from the sites you visited. Next time you reopen a page, the displayed images will be the local copies created and stored by your browser.
General instructions for deleting the cache for all browsers
a. Chrome, Firefox, Opera: Click SHIFT+CTRL+DELETE at the same time. Select only the Cache option from the menu, and be sure that the time range covers all your browsing history.
b. Or, look for the menu button. In most cases it is a button decorated with three lines or three dots. Once the menu is opened, go to the History submenu and choose Everything/Beginning of time/ – you got the idea, select Cache and click Delete.
c. If you have a particular browser/OS combination check this page:
Remember: Usually, the clear private data menus have all options checked. If you want to clear only the cache, then uncheck the rest of the options. If you also delete the cookies, then you will be logged out from your sites.
How to clear Firefox cache
1. Clear private date shortcut SHIFT-CTRL-DELETE.
2. Click the three line button to open the Menu and choose History. In the next panel select Clear recent history.
3. How to clear Firefox cache – the official guide.
Hot to flush the Chrome cache
1. The simplest way to delete the Chrome cache: Input the follow command in your browser address field and click Enter: chrome://settings/clearBrowserData
2. Or you could open the Settings menu (three dots button from the right Edge of the toolbox bar), click More Tools, and Clear Browsing Data.
3. CTRL+SHIFT+DELETE works for Chrome too. Just be sure to select the desired
4. The official guide: Clear cache and cookies.
How to clear Opera cache
a. To display the Clear browsing data menu, type opera:cache into the address field.
b. Or, open new tab, click the clock icon from the left toolbar and Clear browsing data afterward.
How to delete Edge cache
1. CTRL+H will open the History menu, and you will know from there.
2. Open the menu by clicking three dots button. From Settings, choose Clear Browsing Data – select the type of private data you want to delete and click on the Clear button.
3. View and delete browser history in Microsoft Edge – Microsoft guide.
Bonus: Here is a complete tutorial on How to clear Safari’s cache and history on Mac
Remember: If you want to be sure that what you see is not a copy of an older version of the webpage, then you need to flush the cache from your browser.
How to flush the cache for the most popular WordPress cache plugins
A decent WordPress cache plugin would allow you to flush the cache. Basically, open the settings of your WP cache plugin and look for a button properly named. But because we often have different ideas about what obvious means, we did some screenshots so you can find the purge cache options with ease.
W3 Total Cache – how to flush the cache.
The easiest way to purge your cache when you have W3 Total Cache plugin installed is to click on the icon added by the plugin in the top nav bar and choose Purge Cache.
You could also look for the Performance menu added by W3 Total cache in your admin dashboard sidebar and choose which type of cache you want to delete.
How to purge cache in WP Fastest Cache plugin
WP Fastest Cache works in a similar manner. Just click on WPFC icon on the top nav bar and select Purge Cache.
As you could see, WP Fastest Cache also adds a shortcut to the settings menu from where you can delete cache.
Hosting and CDN caching solutions and how to flush them
It would be too simple to have to deal with only two types of cache, so we have two more: hosting cache solutions and CDN cache. Big hosting companies have such solutions and the good news is that many of them integrate these solutions into your WordPress dashboard.
Tip: Some hosting providers add a ~ Flush cache button right on your WP dashboard’s top nav bar.
1. Cache solutions from hosting providers:
Siteground cache solution is called SuperCacher and here is how you can flush it:
GoDaddy’s instructions for deleting the cache could be read here:
Dreamhost managed WordPress plans are called Dreampress, and it comes with Varnish HTTP Purge plugin which helps you to clear the cache:
2. Popular CDNs
Optimized images and cache
Having proper cache plugins or solutions is important for your site loading speed, but you also need to have your images optimized. Otherwise, your resources will be unwisely spent, your visitors will be unhappy, and you will certainly lose money.
You could try any image optimization plugin for WordPress, but we believe that you reached the right place.
Sign-up for a free monthly subscription (100 credits/month) and test WP ShortPixel plugin. If you need more, we have a competitive pricing policy:
You can also freely optimize your images with our online compressor