4 Best Image File Types to Optimize your Website for Image Search

For any WordPress site, you might have been wondering which image file type is the best? Should you use JPG or PNG or WebP? We will help you in deciding which image file type is suited for your WordPress site.

Besides, we will also cover the factors influencing your decision, the best available image file types, and finally, reveal some best practices to be kept in mind before taking that final call.

Factors to Consider Before Choosing Image File Type

Choosing the proper image file type matters a lot since it directly affects your website performance. It can help you rank well on organic search.

  • Speed & Performance — Some image file types occupy more space than others. By using large image formats, you might make your website slow and add to server loads. To ensure better page speeds and optimal user experience (UX), it is best to go with lighter images.
  • Responsive Design — Nowadays, your website has to render well across devices. Your images need to look great across screens of varying resolutions. With this in mind, it is better to design a website that uses responsive image file types that are supported across devices.
  • SEO Score — Page speed has a direct impact on the SEO ratings of your site. Choosing high-quality and SEO ready images helps in setting up your site for higher SEO scores.
  • Consistency — It is a good practice to stick to one main image file type. You can have one or two preferred formats and try other formats only on an on-demand basis.

Image Formats That Make Website User-Friendly

The two most widely used image graphic components making up any picture are raster graphics and vector graphics.

Raster graphics store information as bitmaps and composed of pixels. It includes nearly all digital images including those selfies on your smartphones. The advantages of these images are that they are cost-effective and can be used across devices without much loss during compression. However, there is some loss in quality during the enlarging of images. Some of the common extensions include .BMP, .GIF, .JPG, .PNG, .WebP, and .TIF.

Vector graphics are widely used in printing services and composed of paths. They are created and saved as a result of a sequence of mathematical statements. They occupy much less space than raster images since they are used to draw continuous and smooth lines. They retain image quality while being compressed as well as enlarged. Some of the widely known extensions include .SVG, .EPS, .AI, and .PDF.

Best Use Cases of Each Image File Type

Let us consider the 4 most popular image formats for websites — JPG, PNG, GIF, and WebP — highlighting the best format based on user requirements. Among these, have you ever wondered which image file type uses lossy compression, which format delivers an image with no background file type? Let’s have a look at them below.


JPG or JPEG stands for Joint Photographic Experts Group. JPG images are ideal for photos and images with vibrant and rich colors. They render really well even when subjected to high compression levels and can display millions of colors.

It supports lossy compression, which results in a slight drop in image quality after optimizing. However, you do have the ability to control the level of compression to ensure high quality and best performance. This image format doesn’t support transparent backgrounds.


PNG, short for Portable Network Graphics, primarily designed to transfer images over the internet. It also displays millions of colors and is heavier than JPG. It works really well with screenshots, logos, infographics, and main header graphics that help in identifying a brand.

PNG supports lossless compression, which means no data is lost during optimization, making these images crisper and sharper than JPG images. Additionally, the PNG image file type supports transparent backgrounds.


GIF is an abbreviation for Graphics Interchange Format and supports both animated and static images. The GIF image file type supports only 256 colors making it unsuitable for color photographs and such colorful illustrations.GIF is used to showcase an animation that is smaller in size than a traditional video format. Most animations on social media are GIF images.

GIF uses lossless compression, supports text labels and transparent backgrounds, making it perfect for simple animations and low-resolution videos.


It is an image file type created by Google’s Web Performance Team to create a suitable replacement for GIF, JPG, and PNG. It was primarily developed for supporting good compression, transparency, and animations.

It supports both lossy and lossless compression, making it a good alternative for PNG. Further, it has better compression than JPEG images while retaining image quality.

Adding WebP Images to WordPress Site

WordPress does not support WebP format. However, you can still use this format on your site using a custom plugin. The WebP Express Plugin allows you to add auto-generated images to your site. It works on all kinds of images, including those on galleries, media libraries, and themes.

As a rule of thumb, PNG is perfect for logos, screenshots, charts, infographics, and high-quality brand images. JPEG is great for small images on your website, as well as photos that have vibrant colors. GIF is amazing for animations and simple videos. WebP is great for web optimization of images to achieve smaller sizes with no significant changes in quality.

Things to Remember While Using Images in Your WordPress Site

We briefly discuss some of the best practices that could help your WordPress site become more effective and functional.

Image Sprites — Combine Multiple Images into a Single Image

It comes from the need to load different aspects of a single image at different times to boost site performance. It dates back to 1975 when it was faster to display a part of a single image than to load new images continually. The idea was to load an image once, rotate it, and display different parts of it, based on the requirement. Some popular software such as SpriteMe, SpriteCow, and Spritepad are used for generating Sprites.

Image Size — Go for Light-Weight Images

As said earlier, the size of the images affects the speed of your website. As such, aim at using light images while preserving visual quality. It is recommended to never resize images using HTML or CSS. Use an image of the required width and height as much as possible. For example, if you need a 200px by 200px image, don’t use an image that’s 500px by 500px. It is also recommended to use images of high-quality and local caching features wherever possible.

SEO for Images — Naming Your Images Right

It is possible to drive more traffic to your website using image SEO. You can do this by naming your images appropriately. For instance, instead of “image001.png,” use “choosing-best-image-file-type.png,” and so on. On top of that, add alt texts to all of your images after uploading. With the help of these alt texts, search engines can now “see” and index your web page in the image search section accordingly.

Keep Improving with the Help of Google Analytics

It all comes down to giving the best experience to your visitors as much as possible. For this, you need to know your visitors and the devices they use to access your site. That way, you can choose the ideal image formats and sizes. For instance, if most of your visitors use the Chrome Browser, you must provide additional features to support the use of WebP image files in WordPress.

In summary, choosing the ideal image file type for your WordPress site is vital as it helps you get the right balance between factors such as speed, UX, performance, SEO, Search Ranking and consistency. If you have further queries, please feel free to reach our experts by emailing us at media@techaffinity.com or get in touch by scheduling a meeting.

Originally published at https://techaffinity.com on January 7, 2020.



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