In the past few weeks we turned on the light on the sensitive topic of the work of on-site optimization, i.e. the management of the images published in order to enhance our ranking: final goal is to try and stand out on Google Images, the parallel Big G’ s searc engine that can be an important source of organic traffic, and not only for online shopping sites. From Google come sto the rescue a guide to the best practices we can apply in order to increase the chance to rank with the search through images.
The best practices for images
It is not the first time that we devote our pages to suggestions on images optimization, even with the indication of specific technical interventions to perform on the site, but now let’s take as compass an official source, the support guidelines for Google Search Console, that lead us through this sensitive as well as useful task.
In the opening, the page written by Mountain View’s technicians promptly reminds us why it is so important to perform these kind of operations: ci ricorda proprio perché è importante eseguire tali operazioni: “Google Images is a way to visually discover information on the web”, that allows users to “quickly explore information with more context around images with new features, such as image captions, prominent badges, and AMP results”. This way, “results can become much more useful, which can lead to higher quality traffic to your site”.
Taking care of and enriching user experience with images
First piece of advice coming from Big G is on the philosophic side: “to boost your content’s visibility in Google Images”, they tell us, we need to “focus on the user by providing a great user experience“, that practically translates into “make pages primarily for users, not for search engines”. There are six stes to face in order to reach this goal:
- Provide good context. Visual contents should always pertain to the page’s topic and it should be better to insert images “where they add original value to the page”. And maybe as redundant remark, Google “discourages pages where neither the images or the text are original content”.
- Optimize placement. Images should be inserted close to the pertaining text and, when fitting, in the top part of the page, that is the most important section.
- Do not embed important text inside Images. According to Google, it is better to avoid “embedding text in images, especially important text elements like page headings and menu items”, given the fact that not all users can access them and translation tools do not work on images. To guarantee maximum accessibility to the contents is better to keep the text on HTML and provide an alternative text for images.
- Create informative and high quality sites. We should always be able to guarantee quality: the “contents on your webpage are just as important as visual contents for Google Images”, because they provide context and make results more interesting. On practical terms, “page content may be used to generate a text snippet for the image, and Google considers the page content quality when ranking images“.
- Create device-friendly sites. Obviously, we also have a referral to the need of planning a site “for all device types and sizes”, that can be mobile friendly and effective for all sites.
- Create good URL structure for your images. As it happens for classical research, “Google uses the URL path as well as the file name to help it understand your images”, and that is why we should “organize image contents so that URLs are constructed logically”.
Elements to check so to enhance the performance
If these are general and always valid tips, the guide then covers with closer attention other elements to check in order to try and enhance the placement of the images in the Research. A first field to manage is the one about page title and description, that as we already know can impact on the choice of the users to click or not on a result.
Page title and snippets influence images CTR
Implicitly (but not that much), Google says that the CTR of images in research is influenced by the supporting info: “Google Images automatically generates a title and snippet to best explain each result and how it relates to the user query”, but the system also used “a number of different sources for this information, including descriptive information in the title, and meta tags for each page”.
Images and structured data
The use of structured data and, in particular, of the product, video and recipe markups (we were talking about this here), can bring huge benefits to a site: Google “can display your images as rich results, including a prominent badge, which give users relevant information about your page and can drive better targeted traffic to your site”. In this case, the image attribute is a mandatory field in order to activate the badge and the multimedial result on Google Images.
Reducing weight and enhancing speed
In order to attract users and then increase the chance of getting more traffic we need “high quality pictures”, that can tempt the click more than “blurry and unclear images”, even in the “result thumbnail”. However, these resources could be a burden on the page’s total size and make the site slower or hard to load, mostly on mobile navigation.
Google’s tip is to “to apply the latest image optimization and responsive image techniques to provide a high quality and fast user experience”. Furthermore, on Google Images as well there is the opportunity to take advantage of the AMP technology, whose characteristic logo with the thunder “helps users identify pages that load quickly and smoothly”: therefore, it could be useful to turn the page hosting the image into AMP format so to reduce loading time.
Taking care of image text
We were saying this before: we also need to optimize all the texts accompanying the images, such as titles, captions, file names and descriptive texts. Google analyzes the page and extract the info relative to the image’s object from the content, including possible captions and titles, and the file name itself can give away what the picture actually represents.
Optimizing the alt text
The alt text or alternative text is instead a portion of text describing an image and improves accessibility for those people unable to see images, “including users who use screen readers or have low-bandwidth connections”. Google uses alt text “along with computer vision algorithms and the contents of the page to understand the subject matter of the image”, and moreover the alternative text “is useful as anchor text if you decide to use an image as a link”, explains the guide.
There are rules to comply with even for this parameter: we need to provide “useful, information-rich content that uses keywords appropriately and is in context of the content of the page” and to avoid any kind of keyword stuffing, that could end to provide “a negative user experience and may cause your site to be seen as spam”.
How to make Google discover all of the site’s images
Moving to a different optimization area, there are some procedures we can apply in order to allow Google to find out all of the images uploaded on the site: first step is to use the semantic markup, because “Google parses the HTML of your pages to index images, but does not index CSS images”.
Useful will then be to use an image Sitemap, providing further details on these resources and mainly on their referring URL: on the contrary of normal sitemaps that have croos-domain restrictions, for images we can also enter URLs toward other domains, and then use CDN nets to load these files.
Formats of supported files
There are some limits to the file formats Google actually supports, that only are BMP, GIF, JPEG, PNG, WebP and SVG. There is though the chance to “inline images as Data URIs”, that embed the element “by setting the src of an img element as a Base64 encoded string”, reducing HTTP requests but at the same time with the risk of “considerably increase the size of the page”.
Images and SafeSearch
Last chapter of the Google guide is dedicated to the sensitive matter of SafeSearch, the setting that “specifies whether to show or block explicit images, videos, and websites in Google Search results”. Site owners must help Google to figure out the nature of the images so to apply the settings whenever fitting.
For those sites including adult images, the strong recommendation is to group these files “separately from other images on your website”, and to use the auto-markup of adult pages and the meta tags
<meta name="rating" content="adult" /> <meta name="rating" content="RTA-5042-1996-1400-1577-RTA" />
that allow not to show users ” results which they don’t want to or expect to see”. Anyway, Google algorithms use “a variety of signals to decide whether an image or a whole page should be filtered from the results when the user’s SafeSearch filter is turned on”, also through machine learning, but the “SafeSearch algorithms also look at simpler things such as where the image was used previously and the context in which the image was used”.