Image SEO for Blogs: Alt Text, Sizing, and Loading Speed

Images are part of SEO

Search engines can't "see" images, but they read alt text, filenames, surrounding copy, and performance signals. Well-optimized images earn image-search traffic and lift your page experience score.

Four optimization areas

1. Write good alt text

Describe the image in one natural sentence with your target keyword — no stuffing.

2. Control size and format

• Export at the actual display size, never the giant original
• Prefer modern formats like WebP / AVIF
• Use different sizes for list thumbnails and in-article images

3. Speed up loading

• Lazy-load everything below the fold
• Set explicit width and height to avoid layout shift (CLS)

4. Filenames and structured data

• Use semantic filenames like ai-thumbnail-guide.png
• Add Article structured data for rich-result eligibility

Relevance matters just as much

Original images closely tied to the copy outrank random stock fills. Generate content-matched illustrations with Peituka, then apply the technical checklist above for the best SEO results.