When an SME invests in search engine optimisation, it thinks keywords, blog posts and backlinks. Almost never images. Yet a significant share of Google searches display visual results, and Google Images remains one of the most widely used search engines in the world. For a craftsman, a restaurant, an online shop or a professional services firm in French-speaking Switzerland, every photo published without optimisation is a missed opportunity.
The good news: image SEO is one of the fastest and cheapest projects in search optimisation. A few hours of methodical work are often enough to unlock traffic your competitors are ignoring entirely. In this article, we walk through the four pillars of image optimisation — file names, alt attributes, the WebP format and image sitemaps — with concrete examples.
Why Google Images Is an Underrated Source of Traffic
Visual search has become second nature. Before choosing a carpenter, a landscaper, a caterer or a hair salon, your future customers want to see the result. They type "custom wooden staircase Lausanne" or "terrace design Geneva" and click straight on the Images tab. If your work does not appear there, a competitor collects the click.
Three reasons explain why SMEs keep neglecting this channel:
- It is invisible in standard reports. Few businesses segment their Search Console traffic by search type, so "Image" traffic flies under the radar.
- Competition is low. On many local searches in western Switzerland, a large share of indexed images lack a proper alt attribute. Standing out takes very little effort.
- Google rewards the overall effort. Optimised images speed up your pages, which also improves your ranking in classic web search.
The Fundamentals: Naming and Describing Your Images
File Names That Speak to Google
Google does not "see" your photos the way a human does: it first reads the text around them, starting with the file name. A file called IMG_4382.jpg conveys no information at all. The same file renamed solid-oak-kitchen-renovation-nyon.jpg signals the subject, the material and the location.
The golden rules:
- descriptive keywords separated by hyphens, with no accents or spaces in the file name;
- three to six words at most, starting with the most important one;
- a location where relevant (town, canton) to capture local searches.
The Alt Attribute: Describing for Google — and for Everyone
The alt attribute is the alternative text displayed when an image fails to load, and read aloud by the screen readers used by visually impaired visitors. It is also the strongest signal you can send Google about what an image shows. Good alt text describes the photo in one natural sentence: "Spiral staircase in solid oak installed in a villa in Morges" rather than "staircase" or, worse, a string of keywords.
Avoid two classic traps: leaving the attribute empty on meaningful images, and stuffing it with keywords ("carpenter lausanne staircase wood cheap quote"), a practice Google penalises. Aim for 5 to 15 words per attribute, unique for every image.
The WebP Format: Faster Pages, Better Rankings
Image weight is one of the main causes of slow SME websites. Yet speed is an official Google ranking factor, measured in particular by the LCP (Largest Contentful Paint) of the Core Web Vitals. The WebP format, developed by Google, produces images that are, according to Google, 25 to 34% smaller than a comparable JPEG and 26% smaller than a PNG in lossless mode.
Fictional calculation: a gallery page with 20 photos of 800 KB each in JPEG weighs 16 MB and takes more than 8 seconds to load on 4G. The same photos converted to WebP and properly resized bring the page under 3 MB and the load time under 2.5 seconds — the threshold Google considers "good".
Conversion requires no technical skills: on WordPress, plugins such as Imagify, ShortPixel or EWWW automatically convert your entire media library for roughly CHF 5 to 10 per month. On a custom-built site, your developer can automate the conversion in about an hour of work.
Discover our services · Chat on WhatsApp
The Image Sitemap: Guiding Google to Your Visuals
An image sitemap is an XML file listing your images and the pages that contain them. It helps Google discover all of your visuals, including those loaded by galleries or sliders that its crawlers sometimes struggle to explore.
On WordPress, the usual SEO plugins (Yoast SEO, All in One SEO, Rank Math) automatically include images in the sitemap: simply check that the option is enabled. Then submit the sitemap in Google Search Console and monitor the "Performance" report filtered by the "Image" search type. That is where you will see, week after week, the impressions and clicks your visuals generate.
Two Typical Scenarios (Fictional)
The Carpentry Workshop in Lausanne
Take a carpenter with 120 photos of past projects, all named "DSC_xxxx.jpg" and without alt text. The job: renaming the files, writing descriptive alt attributes, converting to WebP, enabling the image sitemap, around a dozen hours of work. In the following months, you can expect impressions on Google Images to grow noticeably in Search Console, followed by additional quote requests. In a trade where a single custom staircase is worth thousands of francs, one order won can pay back the investment several times over.
The Online Shop in Geneva
Take a home decor shop with 400 product pages and slow pages on mobile. After converting the entire catalogue to WebP, implementing lazy loading and rewriting the alt attributes on the best-selling products, the LCP can drop back below the 2.5-second threshold Google considers "good". Over a quarter, you can expect more organic traffic, more impressions on Google Images and a better mobile conversion rate: for a shop that already generates regular online revenue, a one-off project like this pays for itself quickly.
Your Five-Step Action Plan
- Audit what you have: export the list of your images and flag generic names, missing alt attributes and files over 200 KB.
- Prioritise: start with the pages that already generate traffic or revenue (homepage, services, best-selling products).
- Rename and describe: descriptive file names for new images, unique alt attributes for every important image.
- Convert to WebP: install an automatic conversion tool and resize images to their actual display size.
- Enable the image sitemap: check its contents in Search Console and review the "Image" report every month.
A Profitable Lever — If You Actually Pull It
Image SEO will never replace a full search strategy, but it is the add-on with the best effort-to-result ratio for an SME: little competition, controlled costs (the amount depends mainly on the number of images and the size of the site) and lasting effects. In 2026, as visual search keeps growing with Google Lens, the businesses optimising their images today are building a lead that will be hard to catch.
At Digital Swiss Agency, we build image optimisation into every SEO audit and every website we create. Curious how many clicks your media library is leaking every month? Let's talk.