Alt text generator for WordPress: how to create AI alt text automatically
Alt text generator for WordPress: create AI alt text automatically, with a view on privacy, cost and context. And how IMG Performer PRO does it.
An alt text generator for WordPress uses AI to write alt text suggestions for your images, either right on upload or afterwards for your whole media library. Five questions decide whether a tool is any good: Where does the image go? Who provides the AI model? Does the tool know the context of your site? Can you review the suggestions? And does it cover your existing images, too?
What does an alt text generator do?
It sends an image to an AI model that can interpret pictures and gets back a short description, which is saved as the alt text. Screen readers read this text aloud. Without alt text, an image stays silent for blind and visually impaired people. Accessibility law adds pressure: the German accessibility act (BFSG), which implements the European Accessibility Act, has applied since 28 June 2025 to online shops and other e-commerce services aimed at consumers. Microenterprises are exempt for services. What a good alt text looks like is explained in Do I need to describe my images?.
Best alt text generators for WordPress: five criteria
Instead of a ranking, compare tools by what matters in practice. The next five sections show how.
Where does the image go?
For the AI to describe an image, it has to see it. With every alt text generator, the image therefore travels to an AI provider, even if the plugin itself runs on your own server. For data protection that means you need a data processing agreement (DPA) with the provider and should know where it processes the images.
With IMG Performer PRO you store your own access to Mistral, OpenAI or Anthropic. We recommend Mistral, a European company with EU servers. Why that matters for alt text is covered in Why a European AI model matters for alt text.
Free or paid?
Many alt text generators work with credits or a monthly quota. Others charge a subscription, and some let you bring your own API key. With your own key you pay your AI provider directly for what you use, so you keep control over model and cost, and there is no quota that runs out. IMG Performer has no credit system of its own. AI alt text is part of IMG Performer PRO (€69 per year or €9 per month). The free version does not include it, and on top of the plugin you pay your AI provider for usage.
Context makes the difference
An alt text only fits when the AI knows what the page is about. A laptop on a travel blog needs a different description than in a software shop. IMG Performer PRO therefore creates a website context: a wizard analyzes existing pages or, for new sites, asks three short questions and turns the answers into a context paragraph. It is placed in front of every alt text request, and you can edit it and have it regenerated at any time. The target language follows the language of your WordPress installation.
Review instead of blind acceptance
AI suggestions are drafts. They land in the normal alt text field of the media library, so you can check and adjust them. Pay special attention to proper names, product names and images with a specific message. A single image can be described again with one click in the attachment detail view, without processing the whole library again.
Existing images and new uploads: how to automate
Automating alt texts means two jobs. New uploads should get an alt text automatically, and existing images need a backfill. IMG Performer PRO does both: AI alt text on every upload and a bulk mode for the entire media library. Alt text, caption and description can be activated individually. How to clean up an existing media library step by step is shown in Make your WordPress media library accessible.
Alt text, captions and SEO
An alt text replaces the image for people who cannot see it. A caption is visible text for everyone. Do not repeat the caption in the alt text. Many people search for “alt text SEO”. An alt text is first of all an accessibility feature. Search engines read it as context for the image, but stuffing keywords into it brings no advantage and disturbs screen reader users. A good generator describes what is visible and what function the image has on the page.
Where IMG Performer comes in
AI alt text is part of IMG Performer PRO (€69 per year or €9 per month). The free version converts to WebP without limits and labels AI images. PRO adds AVIF, AI alt text on every upload, bulk processing and the retroactive check of existing images. More at img-performer.enfants.de.
Disclaimer
As of October 2026. This article is an overview, not legal advice.
Frequently asked questions
What is an alt text generator?
A tool that suggests alt text for images using AI. In WordPress it usually works on upload or as a bulk run over the media library and writes the suggestion into the alt text field.
Is an alt text generator GDPR compliant?
That depends on the provider and the data path. The image is sent to an AI provider to be described. You need a DPA with the provider and should know where it processes the data. With IMG Performer PRO you choose the provider yourself, Mistral with EU servers is recommended.
Do I have to review AI alt text?
Yes. The suggestions are a draft. Check proper names, product names and images with a special message first.
Do I need an API key for IMG Performer?
For AI alt text in PRO, yes. You store your access to Mistral, OpenAI or Anthropic. The costs arise at the provider, IMG Performer has no credit quota.
Does an alt text generator help with SEO?
Alt text is mainly an accessibility feature. Search engines read it as context, but keywords bring no advantage.
Should I automate alt text or write it by hand?
Automation covers the volume, a human check covers quality. Let the generator do the first draft for every upload and review what matters.