How do I optimize images for SEO?

How to improve image SEO

Google has gotten better at understanding images, but it doesn't process every one. The words you attach to a picture are still the most reliable way to tell Google what it means.

Describe every image with alt text

The main thing you do for image SEO is add

alt text

: a short written description of what the image shows. In SimDif, you'll find an

Image description

field just below the image editor. Fill it in for every image you add, then Publish.

Alt text is also read aloud by screen readers to visitors who can't see the image, so the same short description makes your site more usable for everyone.

The best alt text ties the image to the page's subject in a few words. "The sourdough we bake fresh each morning" is better than "a loaf of bread", because it tells Google how the image relates to your business.

Show your alt text as a caption

Below the description field, there's a "Show" toggle. Enable it and the description becomes a visible caption under the image, read by Google, read by your visitors, and also shown in the lightbox slideshow when an image is tapped.

Keep images relevant to the page

Google reads the text around an image, including the block title, nearby paragraphs, and the caption, to understand what the picture shows and how it fits the page. An image that sits next to text on the same subject reinforces that context. An off-topic image gives Google nothing to go on.

Using your own photos rather than generic stock images is usually best, but mostly for your visitors: a real photo of your work, your shop, or your products builds trust in a way a stock image can't. Google won't penalize you for stock photos, but the people deciding whether to trust you might.

Balancing speed and quality

SimDif automatically creates the right sizes for each image block, so your pages load fast. What it can't do is improve on the file you give it, so two things are worth checking before you upload:

1. File format:

SimDif keeps images in the format you upload. For photographs, a JPG is usually much lighter than a PNG, with no visible difference. So, saving a photo as a JPG first usually makes your page faster. (PNGs are better for logos and graphics, and support transparent backgrounds.)

2. Big enough for every screen:

An image that looks sharp on your phone can look blurry on a desktop computer. This catches people out most with the header image, so start from a larger, good quality original when you can.

A note on filenames

The filename of an image counts a little too. sourdough-bread-melbourne.jpg gives Google a small extra clue compared to IMG_4429.jpg.

For now, SimDif doesn't let you keep custom filenames once an image is uploaded. It's something we plan for the future. In the meantime, a good description on every image is doing the work that matters most.