Fix Your Image SEO in 20 Minutes: The Quick Wins Most Websites Miss

Rename your image files, write real alt text, and compress everything — that's 80% of image SEO, and most websites skip all three.

I audit dozens of sites a year. And I'd estimate 90% of them have images named things like IMG_4738.jpg or Screenshot 2024-03-12 at 10.43.22 AM.png. Their alt text is either missing entirely or says “image” — which is the same as saying nothing. And their 4MB hero images are silently destroying their page speed.

Here's why this matters: Google can't “see” your images. It reads file names, alt attributes, and surrounding context to figure out what an image is about. When you leave those blank or generic, you're invisible in Google Images — a traffic source that accounts for over 20% of all Google searches. You're also hurting your technical SEO by bloating page weight and slowing load times, which drags down your entire site's performance.

The fix takes about 20 minutes for most pages. Do it once, build the habit, and every image you publish from now on works harder for you.

How to Fix It: Step by Step

Step 1: Rename Your Image Files Before Uploading

Your file name should describe the image in plain English, using hyphens between words. No underscores, no spaces, no random strings.

• Bad: IMG_4738.jpg
• Bad: hero_banner_final_v2_REVISED.png
• Good: chicago-skyline-from-navy-pier.jpg
• Good: homemade-sourdough-bread-cooling-rack.jpg

Be descriptive and specific. If the image shows a product, include the product name. If it shows a place, name the place. Think about what someone would type into Google Images to find this exact photo.

Step 2: Write Alt Text That Describes, Not Stuffs

Alt text serves two purposes: accessibility for screen readers and context for search engines. Write it for a human who can't see the image.

• Bad: alt="" (empty)
• Bad: alt="image"
• Bad: alt="best Chicago SEO consultant SEO services Chicago SEO expert"
• Good: alt="Kevin Mahoney presenting an SEO workshop at a Chicago marketing conference"

Keep it under 125 characters. Be specific. Include a relevant keyword only if it naturally fits the description. If you have to force it, leave it out.

For decorative images (background patterns, dividers, purely aesthetic elements), use alt="" intentionally. That tells screen readers to skip it. Not every image needs alt text — but every meaningful image does.

Step 3: Compress and Convert to Modern Formats

This is the one that moves the needle on page speed. Uncompressed images are the single most common reason I see slow-loading pages during site health audits.

1. Run your site through PageSpeed Insights — look for the “Serve images in next-gen formats” and “Efficiently encode images” opportunities.
2. Convert images to WebP. It delivers 25-35% smaller files than JPEG at comparable quality. Use Squoosh for one-offs or ShortPixel/Imagify plugins if you're on WordPress.
3. Set a max width. If your content area is 800px wide, there's no reason to upload a 3000px-wide image. Resize before uploading.
4. Add width and height attributes to your <img> tags. This prevents layout shift (CLS), which is a Core Web Vitals metric Google uses for ranking.

Your target: no single image over 200KB on a standard content page. Hero images can push to 300KB if needed, but question whether you truly need that 1920px background.

Step 4: Add Lazy Loading

For any image below the fold, add loading="lazy" to the img tag. One attribute. It tells the browser to only load the image when the user scrolls near it. Most modern CMS platforms handle this automatically now, but verify it's actually working.

Do not lazy load your above-the-fold hero image or LCP element — that will hurt performance, not help it.

Watch Out For This

Don't go back and rename files that are already indexed and earning traffic without setting up proper 301 redirects for the old image URLs. Renaming a file on your server without redirecting the old URL creates a 404. If that image was appearing in Google Images and driving clicks, you just killed that traffic. Rename files going forward. Only rename existing files if you're willing to redirect.

Go Deeper

Google's own Google Images best practices documentation is the definitive resource here. It's dry, but it's accurate and current. Read it once, bookmark it, and reference it when you're unsure.

Now go pick your five highest-traffic pages, audit the images, and fix them. Twenty minutes. Real results.