How to add alt text to all images in WordPress

Home › Guides › WordPress alt text·Updated August 2026

If you have run a WordPress site for a while, your media library is probably full of images with an empty alt field. It happens to everyone. You upload a photo mid-post, you are focused on getting the article out, and the alt box stays blank. A year later there are four hundred images and no realistic way to go back through them by hand.

The frustrating part is that WordPress will not fix this for you. It copies the filename into the title field when you upload, which can look like the job is done. It is not. The title is a different field from the alt text. Screen readers skip it, and so does Google. The work is still waiting.

Below are the three ways to actually get alt text onto your images, and how to decide between them.

Quick answer: pick by how you want to spend the time

• Writing every description yourself: the built-in editor is already there. Fine when you have a handful of images and know exactly what each one needs to say.
• Typing faster in one screen: a bulk-edit plugin gives you a spreadsheet view, so you are not clicking into each attachment one at a time. You still write every line.
• Reviewing instead of writing: an alt text generator drafts the descriptions and you edit the ones that matter. Editing a sentence takes a few seconds. Writing one from scratch takes longer than people expect, and that is why the field stays empty in the first place.

Size is not really the deciding factor. Twenty images with empty alt text is still twenty blank boxes. They are rarely blank because the site got too big. They are blank because writing descriptions is dull work that never feels urgent.

The four fields WordPress gives every image

Before picking a method, it is worth knowing that alt text is only one of four fields WordPress keeps for every image. Most guides stop at alt text, which leaves three boxes empty.

Alt text

The description read aloud by screen readers and used by search engines when the image cannot be displayed. This is the one that matters most for both accessibility and image search.

Title

Shown as a tooltip on hover in some themes. WordPress prefills it from the filename, which is why so many sites end up with titles like DSC00194. Low impact, but worth cleaning up on pages that matter.

Caption

Visible text printed under the image in most themes. Because it appears on the page, it is real on-page content that search engines read like any other text. Useful on galleries, recipes, and product shots.

Description

Longer text saved with the image. WordPress builds a separate page for every image you upload, and this text appears there. Most people ignore it, but it gives search engines more to read.

If you are going to touch every image anyway, filling all four is barely more work than filling one. It is the difference between images that only tick the accessibility box and images that also bring in search traffic.

Method 1: The built-in editor

WordPress does let you set alt text, one image at a time. Open Media in the admin sidebar, click an image, and type into the Alt Text field near the top. It saves on its own. The title, caption and description boxes sit directly beneath it. In the block editor you can also select an image block and set alt text in the block settings on the right.

WordPress has no button that does the whole library at once. That is the thing people keep searching for and not finding. The list view in the media library gets you slightly closer, but you are still handling one image at a time. For a small site that is fine. For anything larger it turns into an afternoon you will not get back.

Method 2: A bulk-edit plugin

A handful of free plugins add a spreadsheet-style view so you can edit alt text for many images on one screen. Media Library Helper and Image Alt Text are two common ones. You install the plugin, open its bulk view, and type alt text down a column instead of clicking into each attachment.

One warning that the plugin listings do not always make loud enough: several of these tools offer a one-click option to set the alt text to the filename. Do not use it. A file called IMG_20231104_2.jpg becomes alt text that reads exactly that. It helps nobody, and if your filenames are packed with keywords it can look like spam to Google. Bulk editing saves you clicks, but you still have to write the descriptions.

Method 3: Let an AI alt text generator write them

An alt text generator flips the job from writing to reviewing. A vision model looks at each image and writes a plain, accurate sentence describing it, and you fix the ones that need your judgment. You still decide the final wording. You are just not starting from an empty box every time.

You know your pages better than any model does, and on the images that carry real meaning you should absolutely edit the draft. The point is that most images on most sites are not like that. A product shot, a screenshot, a stock photo breaking up a paragraph: those just need an accurate description, not a carefully written one, and that is the part worth handing off.

There are two kinds of these tools, and they work quite differently.

Media-library plugins

These run inside WordPress and work through the files in your media library. The convenient part is that they save the text straight into the image, so there is nothing to copy over afterwards.

The limit is what they can see. A plugin looks at the image file on its own. It does not know which page the image is used on, so it can describe the picture, but not why the picture is there. It also works through your whole library, including old images that are not on the site any more.

Site crawlers

Tools such as Image SEO Lab open your pages the way a visitor does, so they see each image where it is actually used. That matters more than it sounds. The same photo can need different alt text on different pages. On a recipe post it should mention the dish. On a camera review, the same photo might need to mention the camera.

Image SEO Lab reads the page around each image, including the heading and the text near it, and writes the description to match. It only looks at images that are on your live pages, and it fills all four WordPress fields rather than just the alt text.

So the choice comes down to what you want most. A plugin is the shorter route, because the text saves itself and you never leave the WordPress admin. A crawler gives you descriptions written for the page the image sits on, which is the whole reason a screen reader or Google reads them. The trade-off is that you copy or import the results yourself.

How to write alt text that earns its place

Whether you write it or an AI drafts it, good alt text follows the same short rules. These are worth knowing so you can spot a weak description when you review it.

• Describe the point of the image, not every pixel. Ask why the image is on that page. A photo on a recipe post should mention the dish. The same photo on a camera review might mention the camera.
• Keep it to one sentence, around 80 to 125 characters. Long enough to be useful, short enough that a screen reader reads it in full.
• Drop "image of" and "photo of". A screen reader already announces that it is an image. Those words just use up space.
• Write for a person first. Alt text is read aloud to people who cannot see the screen. If it reads naturally to them, it reads fine to Google too.

Here is the difference in practice, for a photo on a page about trail running shoes:

• Weak: shoe.jpg
• Better: A blue trail running shoe with a lugged sole, photographed on wet rock.

Check your work before you move on

However you add alt text, it is worth checking what is left. Our free alt text checker reads any page you give it and lists the images with nothing in the alt field, along with the ones that ended up with a file name instead of a description. To do the same by hand, right-click the page, choose View Page Source, and search for alt="". Either way you are checking one page at a time, so on a site with a hundred posts a full scan is the faster route.

Running a store as well? Shopify keeps its alt text in a different set of places, and its themes fill the empty ones with the product title, which hides the problem. The Shopify version of this guide covers that.

Frequently asked questions