Image SEO: Alt Text, File Names and Smaller Photos

By Neha·Published October 6, 2026

A boutique owner uploads forty photos of her new festive collection straight from her phone. Each file is called something like IMG_4821.jpg. Each one is about 5 MB. None has a description.

To her customers the page looks lovely, eventually, once it finishes loading. To Google it is forty blank rectangles with meaningless names, on a page so heavy that half the visitors on mobile data give up before the second photo appears.

Image SEO is the fix for all three problems, and it comes down to three small habits: name the file properly, describe the picture in words, and shrink it before you upload. None of it needs a designer. Below are the habits, each with wrong and right examples you can copy.

Why images matter more for small businesses than for anyone else

A law firm can get away with a site that is mostly text. A bakery, a salon, a jeweller, an interior designer or a resort cannot. People buy with their eyes, and the photos do the selling.

That makes images both your biggest asset and your biggest risk:

• Images are usually the heaviest thing on a page. On most small business sites they are the main reason the page is slow.
• Google Images is a real source of customers for anything visual. Somebody searching "bridal mehndi designs full hand" is looking at pictures, not reading articles.
• Google cannot reliably tell what is in a photo from the pixels alone. It leans on the words around the picture, the file name and the description you give it.

Habit one: give the file a real name

The file name is the first clue Google gets. Rename the photo before you upload it, because on most website builders you cannot change it afterwards without uploading again.

The rules are short:

1. Use plain words that describe what is in the picture.
2. Separate words with hyphens, not spaces or underscores.
3. Use lower-case letters only.
4. Keep it to three to six words.
5. Mention the place only when the place is really part of the photo, like your shopfront.

Do not cram in every keyword you can think of. A file called best-cheap-saree-shop-near-me-saree-online-buy.jpg helps nobody.

Habit two: write alt text a blind customer could use

Alt text is a short written description attached to an image. Visitors normally never see it. It is read aloud by screen readers, the software that blind and low-vision people use to browse, and it is shown in place of the picture when the image fails to load on a weak connection. Google reads it too.

So alt text has two audiences, and the trick is to write for the human one. Describe the photo as you would to a friend on the phone.

A few practical points:

• Aim for one sentence, roughly 8 to 15 words. Screen readers read all of it, so do not write a paragraph.
• Put the important detail first. Product type, colour, material.
• Use your keyword only if it truly describes the photo. If the picture is of your storefront, "dental clinic in Indiranagar" belongs there. If it is a stock photo of a smiling woman, it does not.
• Leave decorative images blank. A divider line or a background swirl should have empty alt text, so screen readers skip it.
• Buttons and logos need alt text too. A WhatsApp icon that links to your chat should say "Chat with us on WhatsApp", not "icon".

Where do you type it? In WordPress, click the image in the media library and fill the "Alternative Text" box. In Shopify, click the product image and choose "Add alt text". Wix and Squarespace have a similar field in the image settings.

To see how many of your current images have nothing, run a page through the image alt text checker. It lists every image with no description, so you know exactly which ones to fix.

Habit three: shrink the photo before uploading

A modern phone photo is around 4,000 pixels wide and 3 to 8 MB. On a website it is displayed perhaps 800 pixels wide. You are making every visitor download a billboard to look at a postcard.

Two things reduce the weight:

Resize. Make the picture only as wide as it will be shown. For most sites, 1,200 to 1,600 pixels wide is enough for a large banner and 800 pixels for a product photo.

Compress. Squeeze the file so it takes less space while looking the same to the eye. A good target is under 200 KB for a normal photo and under 400 KB for a full-width banner.

The format matters as well. JPEG suits photographs. PNG suits logos and graphics with flat colours or transparent backgrounds, and is a poor choice for photos because the files are huge. WebP is a newer format that all current browsers support and that typically comes out a quarter to a third smaller than JPEG at the same quality.

The image compressor and WebP converter handles up to 30 photos at once: it compresses them, converts them to WebP or JPEG, gives them names Google understands and drafts their alt text. The work happens in your browser, so your photos are not uploaded anywhere. For Google Business Profile photos, which have their own size rules, use the photo resizer for Google.

Afterwards, test the page. The PageSpeed and Core Web Vitals checker shows Google's speed score on a phone and tells you which images are still too heavy. Our guide on how to improve website speed explains the scores.

Smaller things that still help

• Put text next to the photo. A product name and two lines of description beside the picture give Google context that the image alone cannot.
• Use real photos where you can. Stock photos appear on thousands of other sites. Your own shop, your own work and your own team are unique, and customers trust them more.
• Add width and height. When a page knows an image's size in advance, the layout does not jump around while loading. Most builders do this automatically. Hand-coded sites often forget.
• Turn on lazy loading. This makes images further down the page load only when the visitor scrolls to them. WordPress does it by default. Keep it off for the first big image at the top, which should load immediately.
• Do not put important words inside pictures. A festival offer designed as one big image, with the price and dates baked in, is invisible to Google and to screen readers. Type the offer as text on the page as well.
• Check your share image. The picture that appears when your link is shared on WhatsApp is set separately. See our guide to fixing a link preview on WhatsApp.

Frequently asked questions

What is alt text in simple words?

It is a short written description of a picture, stored in the page's code. Screen readers read it aloud to people who cannot see the image, browsers show it if the image fails to load, and search engines use it to understand what the picture shows.

How long should alt text be?

One clear sentence is enough, usually 8 to 15 words and under about 125 characters. Long descriptions are tiring to listen to. If a picture needs a long explanation, such as a chart, put that explanation in the page text instead.

Does image SEO help local businesses rank?

It helps in two ways. Faster pages do better on phones, where most local searches happen, and well-described photos can appear in Google Images for product and service searches. It is a supporting factor, not a replacement for a complete Google listing and good reviews.

Should I convert all my images to WebP?

For new uploads, yes, if your platform accepts it, because the files are smaller at the same quality. For existing images, convert the heaviest ones on your most visited pages first. There is no need to redo an entire site in one go.