comparison
Most alt text apps never look at the picture. One does.
Three of the four write from the product title, the brand and a template, and put the same line on every image of the product. AltText.ai reads the image too, and saves without asking. Fillwell describes each image from the image, shows you the result next to the photo, and asks you to approve. This page puts five options side by side, including where another app is the right call.
the short version
Pick by how many photos each product has.
Three of the four are rated well, and one is too new to have reviews. The differences are whether the text comes from the picture, and whether you see it before it saves.
One photo per product, clear titles
A free template app. AltKing writes honest text from the title and syncs daily. Nothing to pay.
Thousands of images a day, nobody to review
An automatic app. AltText.ai reads the image, writes on create and update, and skips alt text you already wrote.
Several images per product, and you care what they say
Fillwell. It describes each image, you approve, and the same scan fills the other five gaps.
side by side
One table, ten rows.
A check means it does it. A dash means it does it with a caveat, written in the cell. A cross means it does not.
| Fillwellone of six gaps | AltText.ai4.5, 141 reviews | AltKing5.0, 207 reviews | AltGenius4.9, 57 reviews | ALTTextifynew, no reviews | |
|---|---|---|---|---|---|
| Looks at the picture | ✓A vision model describes what the image shows | ✓Reads the pixels plus product title, vendor and keywords | ✕Template: title, type, tags, brand | ✕Template from product data | ✕Writes from title and brand |
| Finds the images with no alt text | ✓The scan counts them, every product, every image | ✓Finds images missing alt text; its dashboard shows what is missing | –Syncs daily | ✓Adds to images lacking alt text | –Bulk-updates existing images |
| Different text per image of one product | ✓Front view, back view, detail shot each get their own | ✓Describes each image | –Variables per variant image | ✕One template | –Same product data |
| You see it before it saves | ✓A page at a time, next to the photo. A paid bulk run saves first, with review and undo after | ✕Runs on settings | ✕Runs on a click | ✕Runs daily | ✕Runs automatically |
| Undo | ✓One row, one page, or all of it | ✕ | ✕ | ✕A review reports its own alt text overwritten | ✕ |
| Keeps alt text you wrote yourself | ✓Only blank alt text is a gap; filled ones are left alone | ✓Skips existing alt text by default | –Settings decide | ✕Overwrites by default | –Settings decide |
| New images as you add products | –The scan finds them; you approve the batch | ✓Automatic on create and update | ✓Daily sync | ✓Daily sync | ✓Automatic |
| Also fills the other empty fields | ✓Categories, details, descriptions, SEO, translations, from the same scan | ✕ | ✕ | ✕ | ✕ |
| Free tier | –200 AI credits once, one per image, page by page | –25 images, then $3 per 50 | ✓Free, template only | ✕$4.99 a month | ✕14-day trial |
| Paid, per 100 images | ✓About $2 on any paid plan, from $20 a month with 1,000 credits | ✓$5 a month for 100 | ✓Free | ✓$4.99 a month, no image cap | ✓$5 a month for 175 |
Prices, review counts and how each app writes its text are from the Shopify App Store listings for AltText.ai, AltKing, AltGenius and ALTTextify on September 22, 2026. AltText.ai's image analysis and skip-existing default are from its own Shopify page and docs. Where a listing does not say, the cell says so.
the first row
Alt text describes a picture. So read the picture.
A screen reader says the alt text out loud in place of the image. Google Images and AI assistants use it to know what the photo is. Text generated from the title tells them what the product is called, which the title already did. Fillwell sends each image to a vision model, gets a description of what is in it, with the product name as a hint, and shows it to you beside the thumbnail.
The scan counts them
Free. Every image on every product with blank alt text.
It describes each image
From the image.
You approve
Thumbnail next to text. Nothing saves until you say yes. Undo anything.
One AI credit per image. The free plan's 200 credits cover 200 images. How Fillwell writes alt text →
good to know
Common questions
Why does it matter whether the app looks at the image?
Alt text is supposed to say what the picture shows. A template that writes "Navy Crewneck T-Shirt, Acme" on every image of that product is fine for the front view and wrong for the size chart, the fabric close-up and the model shot. Screen readers read it aloud; Google Images and AI assistants match on it. Fillwell describes each image from the image.
Are the free template apps a bad choice?
No. If your products have one photo each and a clear title, a template is honest text at zero cost, and AltKing does it well. The gap opens with several images per product, lifestyle shots, and detail photos, where a template says the same thing five times. AltText.ai closes that gap too, at a price per image, without the review step.
What about images that already have alt text?
Fillwell treats blank alt text as the gap and leaves the rest alone, so anything you or a photographer wrote stays. AltText.ai skips existing alt text by default. Some of the template apps overwrite unless a setting says otherwise, and one has a review reporting exactly that.
Does Fillwell run automatically on new images?
Not by itself. The scan finds new images without alt text as your catalog grows, and you approve them in a batch, one product's images at a time or a page at a time, with undo. If you want text written the second an image is uploaded and never look at it, the automatic apps do that and Fillwell does not.
What does it cost?
The scan is free on every plan. Writing alt text is one AI credit per image, so about $2 per 100 images on a paid plan, and the free plan's 200 credits cover 200 images. You see the count before you run anything. Bulk fills across the whole catalog need a paid plan; page-by-page works on free.
Which is right for me?
One photo per product, tight budget: a free template app. Many images per product and you want to read the text before it publishes: Fillwell, and you get the other five gaps in the same scan. Thousands of images a day with nobody to review them: AltText.ai, which reads the image and runs on its own.
you're in control
Approve each change, or bulk fill and undo anything.
AI can do this work. It shouldn't do it alone. Fillwell is built that way on purpose.
- You guide it. Tell it what to do in plain words.
- It skips when unsure. It never guesses into your live store.
- You can undo anything. One row, one page, or all of it, for 30 days.
Your store. Your decision.
Get the material from the @description.
explore fillwell
See everything Fillwell can do.
One free scan finds the gaps. Then Fillwell fills them, and you approve or undo. Start anywhere.
See how many of your images have no alt text.
Scan free. See the count. Then decide which tool fits.
Free scan · public store only · no install needed.