Help and documentation
SEO Medium impact Easy 1–2 min per image
Images and alt texts
Images need an alt description, a modern format, and compression.
What it is
The alt attribute is a text description of an image. It is read by search engines (which can't see the image) and by screen readers, and it is shown when the image fails to load.
Why it matters
Alt texts help rank in image search and make the site accessible. Unoptimized images (large JPEG/PNG without compression) are the most common cause of slow loading and a worse speed score.
How to do it
- 1Add a descriptive alt to every content image (decorative ones can have alt="").
- 2Describe what is in the image naturally and, where appropriate, with a keyword — not "image1.jpg".
- 3Use modern formats WebP/AVIF instead of JPEG/PNG (25–50% smaller).
- 4Compress and resize to the dimensions actually needed; add lazy loading for images outside the visible area.
Example
Wrong
<img src="DSC_0042.jpg">Correct
<img src="kids-winter-jacket-blue.webp" alt="Kids' winter jacket in blue with a hood" loading="lazy" width="600" height="800">Conclusion
Handle images on two levels: alt texts (SEO + accessibility) and weight optimization (speed). Both are easy and bring a double benefit. A modern format + compression + lazy loading often raise the speed score significantly on their own.
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