In this guide · 8 sections
- 01What alt text is for: accessibility and search
- 02Which images need alt text, and which should be empty
- 03A simple formula for product image alt text
- 04Using AI to draft alt text in bulk, safely
- 05Bulk editing alt text in Shopify and WordPress
- 06Alt text checklist before you finish
- 07Do it yourself or get help?
- 08Frequently asked questions
Short answer
Give every meaningful image a short, specific description of what it shows, such as 'Blue linen shirt, short sleeves, front view', ideally under 125 characters. Give decorative images empty alt text. AI can draft them in bulk; a person checks each before a CSV import.
What alt text is for: accessibility and search
Alt text has two jobs that point the same way. For accessibility, the W3C's Understanding 1.1.1 Non-text Content explains that non-text content needs a text alternative, and that pure decoration should be implemented so assistive technology can ignore it. Our WCAG guide for Singapore websites covers the wider standard.
For search, Google's image SEO best practices say alt text is the most important attribute for providing metadata about an image, that Google uses it with computer vision and the page content to understand the image, and that alt text should be useful, information-rich and in context, without keyword stuffing.
| Example from Google | Rating | Why |
|---|---|---|
| No alt attribute at all | Bad | Nothing for screen readers or search |
| 'puppy dog baby dog pup pups puppies...' | Bad | Keyword stuffing; Google says it may look like spam |
| 'puppy' | Better | Correct but vague |
| 'Dalmatian puppy playing fetch' | Best | Specific, describes what is actually shown |
Which images need alt text, and which should be empty
The W3C's alt decision tree is the quickest way to decide. In short:
| Image type | What the alt text should say | Shop example |
|---|---|---|
| Image inside a link or button | Where the link goes or what the button does | Logo linking home: 'Shop name home page' |
| Informative photo | A brief description of what it shows | 'Rattan pendant lamp, 40 cm, natural colour' |
| Chart or complex image | A short summary, with the full data elsewhere on the page | Size chart: summary plus an HTML table |
| Image repeating nearby text | Empty alt | Icon next to the words 'Free delivery' |
| Purely decorative | Empty alt | Background textures, dividers |
Empty alt text means the attribute is present but blank (alt=""), which tells screen readers to skip the image. Leaving the attribute out entirely is different: the W3C's decorative images tutorial notes that some screen readers then announce the file name instead.
A simple formula for product image alt text
For product photos, a consistent pattern keeps hundreds of descriptions useful and quick to check.
- Product type and key attribute: 'Linen shirt', 'Stainless steel water bottle'.
- Colour, material or size where visible: 'blue', 'bamboo lid', '750 ml'.
- What makes this photo different: 'back view', 'worn by a model', 'close-up of stitching', 'in a kitchen'.
- Leave out: prices, 'best', 'buy now', the shop name on every image, and keyword lists.
| Weak alt text | Better alt text |
|---|---|
| IMG_2041 | Blue linen shirt, short sleeves, front view |
| shirt shirt linen shirt mens shirt singapore | Blue linen shirt, back view showing yoke seam |
| Product photo | Close-up of coconut shell buttons on blue linen shirt |
| Our bestselling premium shirt! | Model wearing blue linen shirt with rolled sleeves |
Shopify's alt text help article says to keep alt text brief and descriptive, with a maximum of 512 characters and 125 or fewer recommended.
Using AI to draft alt text in bulk, safely
Image-capable AI models can describe a photo in a sentence, which makes them good at a first draft for hundreds of images. They also make confident mistakes: wrong colours under shop lighting, guessed materials, or 'a woman holding a phone' when the product is the phone case.
Export a list of images
From your shop or CMS, export image URLs with the product name, variant and any existing alt text.
Give the AI your formula and product data
Ask for alt text under 125 characters, starting with the product type, using the product name and variant from your data rather than guessing.
Ask it to flag decorative images
Banners, patterns and icons beside text should come back as 'empty' rather than a description.
Review every line
A person checks colour, material and what is actually shown, and fixes wording. Ten seconds per image is realistic once the pattern is set.
Import in batches
Upload 50 to 100 at a time, check a few product pages, then do the rest.
The same review habit applies to AI product copy; our guides to AI product descriptions and the Shopify SEO checklist cover the rest of the product page.
Bulk editing alt text in Shopify and WordPress
Both platforms let you edit one image at a time; for hundreds, use the bulk route.
Shopify
- One image: Products, open the product, click the image, Add alt text
- Bulk: export products to CSV, fill the Image alt text column, re-import
- Alt text up to 512 characters; 125 or fewer recommended
- Test the import on a few products first
Best for: Shops with many products and variant images.
WordPress and WooCommerce
- Media Library: each image has an Alt Text field
- Bulk: a media or SEO plugin, or a developer script
- Spot-check older posts after the change
- Back up before running any bulk update
Best for: Blogs and WooCommerce stores.
Shopify's CSV import guide documents the Image alt text column. WordPress documents the Alt Text field on its Media Library screen. After any bulk change in WordPress, open a few older posts and product pages to confirm the images on the page show the new alt text.
Alt text checklist before you finish
Alt text is one part of image SEO; file names and file sizes matter too. Google suggests short, descriptive file names such as my-new-black-kitten.jpg instead of IMG00023.JPG, and our image compression guide covers the speed side.
Image alt text check
Do it yourself or get help?
For a few dozen products, typing alt text by hand in Shopify or WordPress is a long afternoon. For several hundred, the export, AI draft, review and import routine above is the sensible path, and the review step is the one not to skip.
Our Speed & SEO Fix (S$390) covers image compression and lazy loading, caching and script clean-up, titles, descriptions and headings, a sitemap and Google Search Console set-up, and broken link clean-up, with a before-and-after PageSpeed report. Tell us in the brief if alt text is a priority so we can scope it with you before work starts.
Frequently asked questions
Short enough to be read quickly: a phrase or one sentence. Shopify allows up to 512 characters but recommends 125 or fewer. Describe what the image shows that matters on that page, such as the product, colour and view, and skip phrases like 'image of'.
Yes. Google's image SEO guidance calls alt text the most important attribute for image metadata and says Google uses it, along with computer vision and the page content, to understand the image. It also warns that stuffing alt text with keywords creates a poor experience and may be treated as spam.
No description, but they should have an empty alt attribute. The W3C's alt decision tree says purely decorative images, and images that only repeat text right next to them, should use an empty alt so screen readers skip them. Leaving the attribute out entirely can make some screen readers read the file name.
Yes, as a first draft. AI models can describe photos quickly, but they misjudge colours and materials and sometimes add claims. Give the AI your product names and variants, ask for short descriptions in a fixed pattern, and have a person check every line before importing them.
Export your products to CSV, fill in the Image alt text column for each image row, and import the file back. Shopify's CSV guide documents the column. Test with a few products first, check the product pages, then import the rest in batches.