Guide

Image SEO: how do alt text, file size and file names help you rank on Google?

This question comes up with almost every business owner we work with — and the answers floating around are rarely complete. Here is what actually works, based on real-world practice.

July 4, 2026

TL;DR

Images play on two fronts: badly optimised, they sink your speed and therefore the experience; well optimised, they open up Google Images traffic and reinforce your pages' relevance. Few levers combine so many gains for so little technical effort. PageOneBoost applies this method for its clients — one-time yearly payment from €300, no monthly subscription, free audit.

What you need to understand

Write useful alt attributes : Alt text describes the image for screen readers and for Google, which doesn't "see". Describe factually what the image shows, working the keyword in when it's legitimate — never a list of keywords.

Name files before uploading : "IMG_4521.jpg" teaches nothing; "bathroom-renovation-leeds.jpg" sets the subject. Make renaming a habit — lowercase, hyphens — before every upload: on most CMSs it's impossible to fix in bulk afterwards.

Compress and serve the right format : Modern formats like WebP or AVIF sharply cut the weight at equal visual quality. Compress systematically and serve dimensions matched to the actual display: a raw camera photo has no place on a web page.

The method, point by point

Lazy-load off-screen images : Lazy loading only loads images as the visitor scrolls near them: the page displays faster. Mind the exception: the main image visible on arrival must load with priority, not deferred.

Favour authentic photos : Your jobs, your team, your premises beat any stock image: they lend the page credibility, stand out in Google Images, and nobody else can publish them. Authenticity is a trust signal too.

Write useful alt attributes
Name files before uploading
Compress and serve the right format
Lazy-load off-screen images
Favour authentic photos

What PageOneBoost does for you

Everything above takes time, method and experience. That's exactly what PageOneBoost does: a free audit to measure your potential, then the complete foundation built — technical, content, Google Business Profile, reviews, authority — to target the first page for the long run.

Our model is simple: a one-time yearly payment, from €300, with no monthly subscription. The service covers 12 months and renews by tacit renewal. 100% white-hat method, measurable results. To talk it through: +33 1 84 80 13 42.

Frequently asked questions

Is the alt attribute really a ranking factor?

It helps Google understand the image and its context, and it's decisive for appearing in Google Images. Its weight on the page's ranking stays modest — but it's a free signal that adds to the others.

Is Google Images traffic worth anything to a business?

Depending on the trade, yes: crafts, interiors, food, products — anything chosen by eye generates image searches that lead to visits. For a purely service-based trade, the main stake remains speed.

Should every image have alt text, including decorative ones?

Purely decorative images can carry an empty alt (alt=""): screen readers skip them cleanly. Save the descriptions for images that carry real information.

Can anyone guarantee the top spot on Google?

No — nobody controls Google's algorithm, and a "guaranteed position" is a warning sign, not a selling point. What can be guaranteed: a proven, 100% white-hat method and measurable progress.

Where should you actually start?

With a proper assessment: indexing, current rankings, Google Business Profile, technical health. That's exactly what PageOneBoost's free audit covers — you know where you stand before investing anything.

Get onto the first page of Google

Free audit, one-time yearly payment from €300, no monthly subscription. PageOneBoost builds your visibility to last.

Request my free audit