Images play crucial role in the performance of websites. Large size images take longer to load that results in poor user experience and hence, poor search engine rankings. So it is very important to use the optimized images. There are several ways to reduce the size of an image, depending on the specific use case and the desired quality of the resulting image.
Compress Images
Image compression is a process that reduces the file size of an image without significantly impacting its quality. Reducing the size by compression does not only helps in reducing loading time on site but also easy for storage and sharing. You can use free online tools such as TinyPNG, CompressJPEG or Kraken.io to compress your images before uploading them to your website. However, choice of the impression tool should be made carefully so that loose the specific details and color accuracy.
Resize Images
Make sure that you are using the appropriate size of the image for the location it is being placed. Avoid using an image that is much larger than you need and then forcibly adding width and height.
Images should be made responsive and size should be rendered as per the device type. You can use several online and offline tools to resize image for different components on webpages like workers in cloudflare, custom code, Content aware fill or seam curving.
Use Lazy Loading and image caching
Lazy loading means that images are only loaded when the user scrolls to the part of the page where the image is located instead of loading all images at once. This can significantly reduce page load times.
Image caching store the images in locally so as to reduce the the need to download them every time they are requested and moreover, reduce amount of data transferred over the network, resulting in faster loading times and lower bandwidth usage.
Use a Content Delivery Network(CDN)
A CDN distributes your website’s content across a network of servers, which can speed up the loading time of your images. When the user sends the requests, CDN helps to fetch the images from the server which is geographically closer.
Use Image Sprites
Image sprites combine multiple images into a single image and help reducing the number of Http requests made to a server and improve page load times. For example: social media images in footer
Reduce number of images
Consider using fewer images on your pages, or reducing the size of your image galleries, as this can also help to speed up your page loading times.
Use Images in Next generation format
Modern image formats, such as WebP and AVIF, are designed to be more efficient than older formats, such as JPEG and PNG. These formats result in smaller image sizes and improve performance.
Remove Metadata
Image metadata like EXIF data(camera settings, data, time, location of image, etc) add extra bits/bytes to the image. Removing this data will decrease the image size without impacting the quality of images. You can use online, offline tools or plugins like adobe photoshop, ExifTool, GIMP, etc. to remove metadata of images. Make sure that you do not remove the meta data that is essential for maintaining the quality.
Use Vector Graphics
Scaling images without loosing the quality is too difficult. Using Vector graphics, it can be achieved. It is created with mathematical equations so it can be scaled easily without losing quality. So choosing vector graphics instead of JPEG or PNG can also help in improving load time.
Use the correct file format
Choosing the image format affects the size and quality of images. JPEG and PNG are considered the correct formats for the images on site. JPEG is generally the best format for photographic images, while PNG is better for graphics with few colors or images with transparency and sharp edges. GIF is good for simple animations.
By optimizing your images, you can reduce page loading times, lower bandwidth usage, improve SEO, and provide a better user experience for your website visitors. However, using the right tools and methods is also essential so as to not impact the details and quality if images.
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