Free Alt Text Generator: 3 Ways to Get Descriptions Without a Subscription
Most “free alt text generator” pages are lead capture forms for a paid product. You upload an image, get a teaser, and hit a paywall when you try to use it on your site. This page is the other thing: three methods that stay free, what each one actually costs in effort, and when a subscription makes sense anyway.
None of them is magic. Alt text is a short, specific description of what an image shows and why it is on the page. A vision model can draft that description in a second; a person still has to approve it.
What “free” really means
AI generation always has a cost somewhere: a free chat tier with usage limits, a provider bill on your own key, or a paid service that bundles it. “Free” here means no subscription and no per-image markup, not zero cost forever.
- Free chat tier: one image at a time, manual copy-paste, fine up to a few dozen images.
- Bring-your-own-key plugin: bulk workflow inside WordPress; you pay the AI provider directly, usually cents per image or less.
- Browser checker: no AI at all — it reviews text you already have.
Method 1: a chat model and a good prompt
If you have ten images and an account with any vision-capable chat model, this is the fastest start. Upload the image, paste the prompt, edit the answer, and put it in the WordPress media library field.
Prompt template: “Write alt text for this image in under 15 words. Describe what the image shows and what matters in this context. Do not start with ‘image of’. If the image contains text, include the words exactly. Output only the alt text.”
It works surprisingly well on product photos and simple illustrations. It is tedious on volume, it has no idea which page the image belongs to unless you tell it, and you will copy-paste every result. For a small site, that may be all you need.
See what an AI alt text generator can and can’t do for the failure modes worth checking: invented details, vague filler, and keyword stuffing.
Method 2: a free WordPress plugin with your own API key
This is the bulk version of method one. A plugin scans the media library for missing alt text, sends each image to a vision provider using a key you control, and shows the draft next to the image. You edit what needs editing and save.
AltMint’s free plan gives you 100 generations a month, a review screen, WooCommerce product images, and support for OpenAI, OpenRouter or Google Gemini. There is no account and no credit card; the only cost is your provider’s usage, and a small vision model is usually a fraction of a cent per image.
- Install the plugin and open AltMint → Settings.
- Choose a provider and paste an API key. Demo mode lets you try the workflow first.
- Run a scan. Only images with empty alt text are listed.
- Generate suggestions, edit the weak ones, save in small batches.
The tradeoff is setup: you need a provider account and a key. After that, the workflow lives where the images live, which is the part that makes volume bearable.
Method 3: check the alt text you already have
If your images already have descriptions, the free win is not generating more — it is finding the ones that say “IMG_2041” or repeat the same keyword five times. A browser-based checker can flag file names, missing context, redundant phrasing, and overlong text without uploading anything.
Use the free alt text checker to review a draft before you paste it in. It is a second opinion, not a grader: the real test is whether a person who cannot see the image would understand the page from the description.
Compare the three methods
| Chat model | Free plugin + your key | Browser checker | |
|---|---|---|---|
| Cost | Free tier limits; paid tier if you exceed them | Plugin free to 100/month; provider usage | Free |
| Volume | A few dozen, one at a time | Bulk, reviewed in batches | One description at a time |
| WordPress context | You supply it | File name, parent page and product title are included | You supply it |
| WooCommerce | Manual | Featured and gallery images | Manual |
| Best for | Small sites, quick samples | Media libraries and product catalogs | Auditing existing text |
Does free alt text hurt SEO?
No model choice decides that; the review step does. AI drafts fail in predictable ways: they describe a generic scene instead of the specific product, they miss text inside the image, or they pad the sentence with keywords. A quick human pass fixes those, and the review-first workflow exists exactly for it.
If you are responsible for accessibility, the same rule applies with higher stakes: wrong alt text can be worse than none, because it confidently misdescribes the image to a screen reader. Treat every generated line as a draft.
Frequently asked questions
Is there a completely free alt text generator?
For WordPress, the plugin is free and unlimited with your own AI key, and a browser checker is free with no account. AI usage itself is billed by the provider you connect, so “completely free” depends on whether you already have API credits or use a free chat tier.
Can I generate alt text for WooCommerce product images?
Yes. A plugin that reads product context can scan featured and gallery images; a chat model can do it one product at a time if you paste the product name along with the image.
How many images can I process for free?
AltMint’s free plan allows 100 generations per month. Manual chat generation is limited by your provider’s free tier rather than by a plugin.
Do I need an OpenAI account?
No. OpenAI, OpenRouter and Google Gemini are supported, and you can run the plugin in demo mode to see the review workflow before choosing a provider.