From the resolution and format to image alt tags, everything plays an important role in the ranking of a website.
Now, while it is known that small resolution graphics load faster and that keyword-rich alt tags are easily readable, there is some dispute between “popular on web” and “SEO-friendly” graphics. Most browsers and OSes will support most graphic formats; however, not all formats will be conducive to your website’s bandwidth allocation, loading time, or suit your business objective.
There are mainly 5 types of graphic formats that are highly popular on the web, and all of them have their benefits and disadvantages as far as SEO is concerned:
JPEG– It’s the most widely used image format and is supported by all popular operating systems, which is highly beneficial from the SEO perspective. However, unlike GIF, JPEG cannot be animated and its excellent resolution may make graphics heavier.
If your requirement is cross-OS compatible graphics to use in small numbers on your website, JPEG is the best choice for SEO-friendly images.
GIF– It’s the ideal image format for logos and animations, the latter of which can be done without any coding so viewers can watch it directly from a browser without any third party plug-in. However, GIF supports only 256 colors and lacks the high-quality appeal of JPEG.
So, if your site requires high-gloss quality images, their purpose being to retain attention, do not use GIF. However, if you want animation effects without the burden of a heavy Flash file, use GIF.
BMP– It’s a popular image format for Windows users, but is not SEO-friendly. Also Bitmap images use up lots of bandwidth that make a site slower.
TIFF– It offers excellent resolution and clarity but is extremely heavy, eat server space and more importantly, can reduce the page loading time. Mac users prefer this format for its richness, but if SERP ranking is more important to you, then avoid it.
PNG– The best quality of PNG is that it’s loss-less. Even compressed, an image remains high-quality despite becoming lightweight. However, PNG is not advisable for graphic design because it is not supported by all web browsers.
Generally, most designers will use JPEG and JIF formats because of their attractiveness, support from multiple-OS and browsers and faster load time.
Author Bio – Hema Gupta a content analyst and marketer at WebGuru Infosystems provides information about image formats to help designers to design SEO-friendly graphics.