Free SEO Tool

Free Alt Text Generator

Upload an image or paste its URL and get three alt text options, written for accessibility first and search second. No sign-up, and the tool tells you what it saw so you can check it.

How to generate alt text

One required step and two optional ones:

1. Add your image

Upload a JPEG, PNG, WebP or GIF, or paste the URL of an image already online. The tool reads the image itself.

2. Add context if you have it

Optionally say what the page is about and give a target keyword. Both are optional and the tool works without them.

3. Pick from three versions

A concise option, a fuller descriptive one, and a keyword version, each with a character count against the 125 character convention.

What is alt text?

Alt text is a short description attached to an image through the alt attribute. Screen readers announce it to people who cannot see the image, browsers display it when an image fails to load, and search engines read it to understand what the image shows.

The useful test when writing it is simple: what would a reader miss if this image did not load? Answer that and you have your alt text. It also explains why "image of a dog" is weak. A screen reader has already said the word image, and "a dog" is not what the reader would have missed.

This matters more than SEO, and being straight about that is worth doing. Alt text exists so that people using assistive technology get the same page as everyone else. Written honestly for that purpose, it also happens to be good for search. Written as a keyword dump, it fails at both.

Alt text examples, weak and strong

The right alt text depends on what the image is doing on the page, not just what is in it:

Image type	Weak	Strong	Why
A meaningful photo	image of a dog	Golden retriever waiting at a front door with a lead in its mouth	Says what is happening, not just what is in frame
A chart	sales chart	Line chart showing organic traffic rising from 2,000 to 9,000 monthly visits across 2025	A chart's meaning is its data, so the alt text has to carry it
A decorative divider	decorative swirl graphic	(empty alt attribute)	Purely decorative images should be skipped by screen readers entirely
An image used as a link	logo	RankSpot home	When an image is a link, the alt text describes where it goes

The third row is the one people get wrong most often. A purely decorative image should have an empty alt attribute, not a description, so assistive technology skips past it instead of narrating a swirl.

How to write alt text well

Six rules that cover almost every case:

Describe the function, not just the appearance. Ask what a reader would miss if the image did not load.
Skip "image of" and "picture of". Screen readers already announce it as an image, so those words waste the listener's time.
Keep it around 125 characters. Longer descriptions belong in a caption or the body text.
Leave alt empty for purely decorative images, so assistive technology can skip them.
If the image contains text that carries meaning, put that text in the alt attribute.
Never stuff keywords. Alt text that reads as a keyword list helps nobody and can be treated as spam.

Alt text and SEO, honestly

Alt text does help search, but it is worth being clear about how much and in what way:

1It is the clearest signal of what an image shows, which is what image search runs on. If image traffic matters to you, alt text is where it starts.
2It adds context to the page around the image, which is a modest benefit rather than a large one.
3Stuffing keywords works against you. Alt text that reads as a keyword list is unhelpful to screen reader users and can be treated as spam.

That is why the keyword field here is optional, and why the tool will tell you when your keyword does not honestly describe the image rather than forcing it in. For the rest of the page, our headline analyzer scores the headline, the meta description generator handles the snippet, and the readability checker covers the body copy.

Accessibility comes first

Alt text is an accessibility feature that happens to help SEO, not the other way round:

Who it is for

People using screen readers, anyone on a slow connection where images fail to load, and readers who have images turned off.

What the guidelines say

WCAG requires a text alternative for non-text content. Those guidelines are referenced by accessibility legislation in many countries.

Check the output

The tool shows what it understood the image to be. If that is wrong, the alt text will be too, so read it before publishing.

Frequently asked questions

What is an alt text?

Alt text is a short written description attached to an image with the alt attribute. Screen readers read it aloud to people who cannot see the image, browsers show it when an image fails to load, and search engines use it to understand what the image depicts. It is written for people first and search engines second.

What is an image alt text?

The same thing: alt text and image alt text are used interchangeably, and both refer to the alt attribute on an img element in HTML. You will also see it called an alt tag, which is technically a misnomer since it is an attribute rather than a tag, but the meaning is the same.

What is alt text writing?

The practice of describing images so that someone who cannot see them gets the same information as someone who can. Good alt text writing is about function rather than appearance: what would a reader lose if this image did not load? Answer that in a sentence and you have your alt text.

How do I write alt text?

Describe what the image contributes to the page in one short sentence, under about 125 characters. Do not start with "image of". If the image is a chart, describe what the data shows. If it is a link, describe where the link goes. If it is purely decorative, leave the alt attribute empty so screen readers skip it.

What is a good example of alt text?

For a photo of a dog at a door, "image of a dog" is weak while "Golden retriever waiting at a front door with a lead in its mouth" is strong, because it conveys the situation. For a chart, name what the data shows rather than calling it a chart. The comparison table on this page has more examples across different image types.

Where to write alt text?

In the alt attribute of the img element, as in img src="photo.jpg" alt="your description". Every CMS exposes this without touching code: WordPress has an Alternative Text box in the media library, and Shopify, Squarespace, Webflow and Wix all have an equivalent field in their image settings.

Can you add alt text to an image?

Yes, to any image on a web page, and you should for every image that carries meaning. The alt text is not part of the image file itself, it is part of the HTML that displays it, so adding or changing it does not require editing the image.

How to write alt text in Word?

Right-click the image, choose View Alt Text, and type your description in the panel that opens. There is also a Mark as decorative option for images that carry no information. PowerPoint and Excel work the same way, and the descriptions carry through when you export to PDF.

How to get image alt text?

To read the alt text already on an image, right-click the page, choose View Page Source or Inspect, and look at the alt attribute on the img element. To write alt text for an image you have, upload it to the tool above and it will describe the image and give you three options.

How do you check for alt text?

Inspect the page source and look for img elements with a missing or empty alt attribute, or use an accessibility auditing tool that reports them in bulk. Note that an empty alt attribute is correct for decorative images, so a missing one and a deliberately empty one mean different things.

Is alt text legally required?

In many contexts, effectively yes. Accessibility rules such as the WCAG guidelines require text alternatives for non-text content, and those guidelines are referenced by legislation including the Americans with Disabilities Act, Section 508 in the United States and the European Accessibility Act. The exact obligation depends on your jurisdiction and the kind of organisation you are, so treat this as background rather than legal advice.

Is image alt text important for SEO?

It helps, though it is a modest factor rather than a large one. Alt text gives search engines the clearest signal of what an image shows, which matters for image search and adds context to the page. The bigger reason to write it well is accessibility, and writing it honestly for that purpose produces good SEO alt text as a side effect. Keyword stuffing achieves the opposite.

Does this tool actually look at my image?

Yes. The image is read by a vision model, which is why the tool reports what it understood the image to show before giving you the alt text. If that summary is wrong, the alt text will be too, and a clearer image usually fixes it.

Is this alt text generator free?

Yes. Several free generations per day, no account and no credits, with all three versions shown every time.

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