Something to keep in mind when writing image descriptions is that it's a completely subjective exercise. There is no formula for crafting the perfect image description. It is not an exact science. Image descriptions will vary between different visuals, creators, and scenarios. As the content author, you have the power to decide what details are important in an image and should be described.
Consider the following questions when writing an image description.
Please remember that all the below tips were written by someone who doesn’t rely on textual information or assistive devices to access digital images.
Focus on describing the physical aspects of your chosen image. Resist the urge to be ornate or overly effusive with your image descriptions, and stick to writing in plain language. You want to avoid having your own opinions or feelings about an image interfere with your ability to write an accurate description. It’s okay to be a little creative with your writing but try to avoid going overboard. Try to be as objective as possible.
Image description for the below example: A man and woman kiss. The man wears a black tuxedo, and the woman wears a white wedding dress and veil that swirls around the couple as they embrace. The bride also holds an elaborate bouquet of white and cream flowers.
How long your image description will be is entirely dependent on the visual you choose for your content. The more complex the visual, the longer the description of it will more than likely be especially if the image features any copy. Again, writing an image description is a completely subjective exercise, no matter how objective you try to be. Just focus on making your image description as accurate as possible and you should do just fine.
Image description for the below example: A Ferris Wheel lit up under a starry night sky at a carnival crowded with people and vendor stalls. Strands of string lights crisscross above where they walk.
It’s already assumed that your image description will be for a photo or image, and a screen reader will more than likely say “image” before or after reading it if you’ve placed it in a designated alt text field.
However, if the visual you’re trying to describe is something like an illustration, a painting, a graphic, or even a screenshot, you can include that in your image description because it gives the user a better idea of how to imagine the visual.
Image description for the below example: Colorful illustration of six different doctors researching and working on an over-sized kidney model.
If a notable person, place, or thing is in your image and it adds context to your content, go ahead and use its proper name in your image description.
Image description for the below example: Mount Rushmore is shown under a hazy blue sky. The cliffside in front of it is dotted with evergreen trees.
Think about the view someone has when they’re looking at your image. Is it a partial view of someone sitting at a table? Do you have a bird’s-eye view of a snow-covered forest? Is your image a close-up of a hummingbird’s fluttering wings? Does your image show a person tilting their head upward towards the sun? Directional or positional information can add important context to your image description.
Image description for the below example: Upward view of ten palm trees swaying in the wind.
If you’re posting a copy-heavy graphic like an event flyer or an image that has text overlayed on it, you’ll need to add information in your image description for all the flattened copy otherwise a screen reader will not be able to read it. Flattened copy is text that has been turned into an object upon being exported from whatever program it was created in. It's sometimes called embedded copy or outlined text as well.
If you drag your cursor over the text on an image and it does not highlight the individual words or characters, that means the text is no longer readable, therefore, it’s also not actionable because it cannot be clicked. JPEG, PNG, and GIF files do not support readable text.
Image description for the below example: Person in a blue windbreaker jacket looking out over a large lake bordered by a steep hillside covered in trees. The word “peace” is ghosted over the image in large, bold letters.
This tip on writing effective image descriptions should be given careful consideration since it was written by a white cis woman. Identity and representation are complex and multi-faceted subjects that should always be treated with respect and care.
If the race, gender, ethnicity, sexual orientation, age, or another identifier for a person is relevant to the overall context of a visual, feel free to add it to your image description. It also helps in this instance to think of your content as a whole. What info is included in the written part of your post? As the content author, do you feel that personal identifiers in your image description would add contextual value to the rest of your content?
For example, let’s say you work for a college and your content is about introducing girls and young women of color to careers in STEM. The race, age, and gender of the people in your images would probably be contextually important.
If you’re unsure about how the subject of an image identifies or don’t want to assume how they identify, stick to using neutral terms such as “person” instead of “man” or “woman.” According to Cooper Hewitt's guidelines for image descriptions, you can use descriptors such as “light-skinned,” “medium-skinned,” or “dark-skinned” to describe the people in an image.
Of course, the best way to ascertain how someone in your image identifies is to simply ask them, if you can. Just make sure to explain to your subject that you’re trying to accurately represent them and their identity in your content.
Image description for the below example: A young Black girl with long curly hair sits in front of a large desktop computer while learning about different careers in science and technology.
It’s better to type out the full name or title of a person, place, organization, or initiative because screen readers don’t always read abbreviations like acronyms and initialisms correctly. Lesser-known abbreviations also don’t add a lot of context to an image.
If you use an initialism in your image description (or any of your digital content for that matter), type out the full name or title first, and then place spaces or periods in between each letter of the initialism.
An initialism is an abbreviation consisting of initial letters pronounced separately. Examples would be U.S.A., S.E.O., and F.B.I. An acronym is an abbreviation formed from the initial letters of other words and pronounced as a word. Examples would be NATO, NASA, and SCUBA.
Image description for the below example: A large group of people sits in rows of chairs at a session for the 2023 Higher Education Social Media (H.E.S.M.) Conference.
If something in your image is significant to understanding the whole visual or post, describe it in your image description. If it’s not, skip it. You don’t need to include every nitty-gritty detail.
The details you include in your image description should be contextually important to painting an accurate picture in someone’s mind.
Image description for the below example: Times Square in New York City is bustling with cars and people at night. Bright digital billboards cover the buildings.
This tip is more applicable to images on traditional websites, as search engines supposedly do not index information from the alt text field on social media platforms yet.
However, keywords in Instagram’s alt text field do supposedly affect search results for posts within the app. Just make sure that you’re prioritizing the accurate description of your image. You should never keyword-pack your image descriptions just to improve the performance of your content.
A block of miscellaneous keywords may affect how accessible your image is because it could make the image description confusing. Instead of keyword-packing, find ways to logically work your keywords into your image description or use hashtags in your caption.
Image description for the below example: A young woman sits on a purple park bench. She wears lightweight athleisure clothing and black Nike running shoes.
Now that you have a better understanding of how to write effective image descriptions, let’s talk about what shouldn't normally be added to them.
First and foremost, a designated alt text field is not a place to hide messages or put additional marketing content. It’s okay to be a little creative when writing image descriptions, but you should focus on making your image accessible.
Remember, the primary purpose of image descriptions is to make visuals accessible through thoughtful and accurate description. That purpose should not be distorted or manipulated for the sake of engagement. Doing so is incredibly ableist.
Other things to avoid in image descriptions:
Questions people often ask about creating accessible images and visuals.
Question: Are there any examples of image descriptions on Accessible Social?
Answer: Yes! You'll find sample social media scenarios paired with images on our Accessible Image Scenarios page. Each visual has an example image description written for it.
Question: Can you mark images on social media as decorative?
Answer: In the traditional web development sense, no, you cannot mark visuals you upload on social media as decorative images. Even without this functionality, the argument could be made that there are very few instances where an image on social media would be considered decorative. Social media content is normally about telling a story in an abbreviated fashion through short copy and eye-catching visuals. If you upload an image to accompany a post, it more than likely has context that viewers should know about, even if it feels minor. You should always write detailed image descriptions for your social media images and never just write "null" or "decorative" in a designated alt text field.
Question: I want to retweet something, but the image doesn’t have alt text. What’s the best way to add it?
Answer: If you're going to retweet a piece of content that doesn't have alt text, quote retweet it and write a description for the image in your tweet. Just make sure that you precede your alt text with the words "image description" or "alt text" so it's clear to a screen reader user what you're tweeting about.