Adding images is a great way to lighten an article and illustrate the most important thing in your text. Images raise your articles and texts to a new level and make them easier to read. But how do you optimise your photos best for the web?
There are essentially two different types of optimisation that you usually talk about in terms of images on the web: optimisation of file size and search engine optimisation.
Optimise the file size of your images
Any image you upload to your site should be in the correct format and size. There are essentially two formats you need to keep track of, JPEG and PNG. JPEG is usually the correct answer when uploading images on the web. It will give you a good compression without tumbling too much on the quality.
Your image is a simple graphics with just a few colors, such as a logo.
You need to use transparency in the image, ie a transparent background.
For simpler graphics, it's best to use PNG-8. This is a format that only fits a few colors but you get small files and the quality is good as long as the graphics are simple.
If you have a photo with many colors and where they tune into each other, it's better to use PNG-24 that can handle more colors. But PNG-24 also provides really big files and therefore you should avoid it for photographic images as long as you do not have to have transparency. For all photographic images without transparency, JPEG will give you the best quality and minimum file size.
When saving your image, it is also important that you save it in the correct size. It's best to upload images in exactly the size you need instead of reducing the image using HTML. Find out what size you need and upload the image right from the start, keeping down the charging time.
Search engine optimise your images
Although search engines have become better at reading and understanding images, it's so far something you need to clarify in the code when you search engine optimises. For a search engine, it's mainly three things you need to think about: the image is relevant to the content, image file name and alt attribute.
Relevance to the text
That the image should be relevant to the content may say itself. Images are good both for readability and for search engine optimisation and the best effect is given if the images illustrate what you want to say in your text. The search engines understand what your image represents using the text around the image. Therefore, it is important, both from a reading perspective and from a search point of view, to keep the images relevant.
So you have a look at the size of your image and which file format will fit best. Now it's time to save your image and upload it to your site. The file name is important for the search engines to understand what your image represents. Therefore try to make it as descriptive as possible - coffee cup.jpg says the search engine more than bild0085.jpg.
The alt attribute
The Alt attribute simply means an alternative text to the image. It is extra important for those with impaired vision and those who use screen readers when the alternative text gives them an understanding of what the image represents even if they can not see it. But even the search engines use the alt attribute to get more information about what the image represents.
Writing a good all-text need not be so difficult. Most content management systems (CMS) have an easy way to add alt attributes to uploaded images. When writing an all-text, it is important to think about what the image shows and like to use keywords. But keyword stuffing is not recommended! Let the text be natural and readable to an ordinary person. Keyword stuffing will keep you away from all aspects of search engine optimisation.
There are many who wonder if they should also give their photos search engine optimised title attributes. It is not something that is necessary for search engine optimisation. The title attribute is not unique to the img tags but can also be used on other tags such as links.
It is not used by the search engines to better understand your images, and so many people do not give their images unique title text. In IE, Internet Explorer, the title text appears when you hover over images but it does not fill any major function beyond that.
Take the time to optimise your pictures
So to summarize, first of all, make sure your pictures illustrate what you want to say in your text. Then it's time to optimise them for the best file size. This avoids the loading of your pages, and the charging rate is a ranking factor. This is extra important. When uploading your photos on the site, it is important to consider giving the search engines good information so they can more easily understand what the images represent. You do this with good and descriptive file names as well as descriptive all-texts.
Take the extra time to write these correctly, your search engine optimisation will benefit and it also improves the experience of your site for those with impaired vision.