Image name vs post title vs focus keyword for alt text
Bialty gives you a choice of signal sources for alt text: focus keyword, post title, image name, or combinations. There is no universal best signal. The right choice depends on the content type, the quality of the metadata, and the goal you are trying to achieve.
This article breaks down when each signal shines, when it fails, and how to decide for your specific site.
Focus keyword as alt text
The focus keyword is the search query you are optimizing the page for, set in Yoast SEO, Rank Math, or All in One SEO.
It works best when the keyword is specific and well-maintained, the page has a clear search target, you want consistency between page SEO and image SEO, and the keyword genuinely relates to what the images show.
For example, a blog post targeting "wooden deck maintenance tips" with photos of deck restoration would benefit from that keyword as alt text. The keyword is specific, relevant to the images, and reinforces the page's search intent.
It works poorly when the keyword is too broad or generic (like "SEO" or "marketing"), when many images on the page show different subjects that a single keyword cannot describe, when the focus keyword field is empty on older content, or when the keyword is more of a category label than a descriptive phrase.
A product page targeting "shoes" with ten different shoe images would produce the same vague alt text on every image. That is neither useful for SEO nor for accessibility.
Post title as alt text
The post or product title is almost always present and usually more descriptive than a short keyword. It captures the editorial intent of the page in natural language.
It works best on editorial content where titles are well-written, on product pages where the product title describes the item clearly, on pages where the focus keyword field is empty or too generic, and when you want alt text that sounds natural and human-readable.
A product named "Men's Trail Running Shoe — Waterproof — Carbon Grey" makes an excellent alt text signal because it is specific, descriptive, and naturally reads like what the image shows.
It works poorly when titles are written for click appeal rather than clarity (titles like "You Won't Believe What Happened Next" are useless as alt text), when titles are excessively long, or when the title has no relationship to the images on the page.
Image name as alt text
Bialty can also use the image filename, cleaned up to remove dimensions, hyphens, and underscores, and converted to title case.
It works best when the media library is well-organized with meaningful filenames, when each image on a page shows a different subject and needs individual alt text rather than a shared page-level signal, when neither the focus keyword nor the title provides useful specificity, and on sites where content managers follow naming conventions for uploaded files.
An image named oak-hardwood-floor-installation.jpg produces alt text "Oak Hardwood Floor Installation," which is descriptive and specific to that individual image.
It works poorly when filenames are generated by cameras or stock photo sites (like IMG_4582.jpg or shutterstock_123456.jpg), when files have been renamed by WordPress or plugins to include dimensions and hashes, or when the naming is inconsistent across the library.
The combined signal: keyword plus title
Bialty also offers a mode that combines the focus keyword and the post title. This produces alt text in the format "keyword, title" and can be useful when neither signal alone is strong enough.
For a post titled "Complete Guide to Indoor Herb Gardens" with a focus keyword "indoor herb garden," the combined output would be "indoor herb garden, Complete Guide to Indoor Herb Gardens." That gives search engines both the exact keyword and the broader editorial context.
Use the combined mode sparingly. It produces longer alt text, and for pages where the keyword and title are already similar, the result can feel redundant.
How to decide for your site
The fastest way to choose is to audit a sample of your actual content. Pick ten representative pages across different content types and check what data is available and how strong it is.
If your site has well-maintained focus keywords on most content, start with the keyword signal. If keywords are sparse but titles are strong, use the title. If your media library is well-organized but your on-page metadata is weak, the image name may be the best starting point.
For WooCommerce stores, the product title is often the strongest signal because it naturally describes the product shown in the image. Focus keywords work well when they are product-specific, but category-level keywords applied to individual product images tend to be too generic.
Using different signals for different content types
You do not have to use the same signal everywhere. If your site has both an editorial blog and a WooCommerce store, you could configure Bialty with the focus keyword for blog content (where keyword discipline is strong) and switch to the product title for WooCommerce (where titles are naturally descriptive).
The commercial plan allows you to select which content types Bialty covers, giving you the flexibility to apply different strategies where they make the most sense.
The Add Site Title option
The commercial scope also includes an option to append the site title to the generated alt text. This produces output like "indoor herb garden, My Garden Blog" and can help reinforce brand association in image search results. Use it judiciously — on sites with a strong brand, it adds value; on sites where the brand name is not a search signal, it adds length without benefit.
The bottom line
No signal is universally right. The best alt text signal is the one that is most consistently available and most relevant to the images on the page. Focus keyword for SEO-driven content with strong keyword discipline. Post title for editorial and product pages with descriptive titles. Image name for well-organized media libraries. And combined modes when a single signal is not enough.
Bialty's value is not that it picks for you. Its value is that it lets you operationalize the choice at scale, test the result on the frontend, and change your mind without consequence.