Image SEO is optimising your images so they load fast, rank in image search, and reinforce what your page is about.
Images are often the biggest thing slowing a page down, and a missed chance to rank. A few habits fix both.
What to optimise
- File size. Compress images and use modern formats like WebP.
- Alt text. Describe the image plainly for accessibility and SEO.
- File names. Descriptive, not "IMG_4821.jpg".
Good habits
- Right-size them. Resize to the dimensions you actually display.
- Lazy-load images below the fold.
- Add captions where they genuinely help the reader.
Worth knowing: Optimising your few largest images usually does more for speed than any other single fix.
Frequently asked questions
How do I optimise images for SEO?
Compress them and use modern formats, add descriptive alt text, use real file names, right-size them, and lazy-load below the fold.
Does image SEO help my rankings?
Yes, modestly. It helps images rank in Google Images, speeds up the page, and reinforces what the surrounding content is about.
What is the best image format for the web?
Modern formats like WebP usually give the best quality-to-size ratio, which is often the single biggest speed win.