Optimize image speed
Posted: Tue Mar 18, 2025 6:02 am
Optimized vs Unoptimized Images in WordPress
Images bring your content to life and help boost engagement. Researchers have found that using colorful visuals makes people 80% more likely to read your content.
However, if your images aren't optimized, they can do more harm than good. In fact, unoptimized images are one of the most common speed issues we see on beginner sites.
Before uploading a photo directly from your phone or camera, we recommend using photo editing software to optimize your images for the web.
In their original format, these photos can have a considerable file size. But depending bc data china on the image file format and the compression you choose in your editing software, you can reduce the size of your image by up to 5 times.
At WPBeginner, we only use two image formats: JPEG and PNG .
Now you might be wondering: what's the difference?
The PNG image format is uncompressed. When you compress an image, you lose information. An uncompressed image will therefore be of higher quality and more detailed. The downside is that the file is larger and therefore takes longer to load.
JPEG, on the other hand, is a compressed file format that slightly reduces image quality, but is significantly smaller in size.
How to decide which aspect ratio to choose?
If our photo or image has many different colors, we use JPEG format.
If it is a simpler image or we need a transparent image, we use the PNG format.
Below is a comparison table of file sizes achieved by different compression tools on a particular image.
Images bring your content to life and help boost engagement. Researchers have found that using colorful visuals makes people 80% more likely to read your content.
However, if your images aren't optimized, they can do more harm than good. In fact, unoptimized images are one of the most common speed issues we see on beginner sites.
Before uploading a photo directly from your phone or camera, we recommend using photo editing software to optimize your images for the web.
In their original format, these photos can have a considerable file size. But depending bc data china on the image file format and the compression you choose in your editing software, you can reduce the size of your image by up to 5 times.
At WPBeginner, we only use two image formats: JPEG and PNG .
Now you might be wondering: what's the difference?
The PNG image format is uncompressed. When you compress an image, you lose information. An uncompressed image will therefore be of higher quality and more detailed. The downside is that the file is larger and therefore takes longer to load.
JPEG, on the other hand, is a compressed file format that slightly reduces image quality, but is significantly smaller in size.
How to decide which aspect ratio to choose?
If our photo or image has many different colors, we use JPEG format.
If it is a simpler image or we need a transparent image, we use the PNG format.
Below is a comparison table of file sizes achieved by different compression tools on a particular image.