Image optimization for Web

Optimizing images before uploading to WordPress can have a huge impact on the website speed. Image optimization is the process of decreasing their file size without loosing quality.

Benefits of image optimization

  • It will improve your page loading speed for a better user experience.
  • It improves your SEO. Your site will rank higher in search engine results. Google is also likely to crawl and index the images faster for Google image search.
  • Smaller image file sizes use less bandwidth.
  • Requires less storage space on our BioSci server. Backing up the site will be faster.


  • Name your images descriptively and in plain language
    Images are indexed by search engines like google, just be sure to use relevant, helpful keywords when naming your images. You could use the generic name (e.g. DCMIMAGE10.jpg). However, it would be much better to name the file ProfessorWoodInLab.jpg.
  • Optimize your alt attributes carefully
    Alt attributes are the text alternative to images when a browser can’t properly render them. The alt attribute not only adds SEO value to the BioSci websites but also helps with accessibility, adding the alt text will reduce the risk of litigation.
  • Choose your image dimensions wisely
    Images should be saved to the size you want them to be viewed on the web. Let’s say you only need the image in the content of an article that is not going to be used as header, then you can use an image editor to adjust the size before uploadingFor banners and header images will be fine to use 1800 pixels width.

    Here are some tips to remember when choosing file types:
    • JPEGs will be your best bet. They provide the best quality for the smallest file size.
    • Avoid use GIFs for large product images. The file size will be very large and there is no good way to reduce it. Use GIFs for thumbnails and decorative images only.
    • PNGs can be a good alternative to both JPEGs and GIFS, the file sizes can still be much larger than JPEG images.If you are only able to get photos in PNG format, try using PNG-8 over PNG-24.
  • Reduce the file size of your images Choose the right file type
    The BioSci multisite has a plugin to optimize the size of the image, however, with large images it won’t be enough. I recommend using the following tools to help reduce the file size (not dimension). These tools reduce by a lot of images, its image size is like 1MB it will reduce it sometimes to 250KB and they keep the dimension and quality. The recommended site for our images is below 200kb.

In case you need help with your images, reducing the size or optimizing, and you don’t have the tools, BioSci Computing can help.