Facebook, Instagram, LinkedIn, Twitter/X, Pinterest, TikTok, Threads, and Bluesky all allow users to manually write custom alt text in some capacity. Alt text can also be added to Facebook and Instagram posts through Meta Business Suite. Snapchat does not currently support alt text.
Click any of the below icons to learn more about adding, editing, and viewing alt text on the desktop and mobile versions of the different platforms.
Some platforms have character limits for their alt text fields. Known character limits are listed below.
If a Facebook image description is a little long, the platform may show a warning that recommends making the alt text less than 100 characters. This warning can be ignored. Alt text should be as long as needed in order to make an image accessible.
Auto-generated alt text created by an artificial intelligence program should never be used in place of a custom image description written by a human.
Meta automatically writes alt text for images uploaded to Facebook, Instagram, and Threads. The brand considers its auto-generated alt text to be an acceptable substitute for not writing custom image descriptions or making an alt text field available. However, auto-generated image descriptions normally exclude important visual details and don’t have the same contextual knowledge about an image that the content author would.
An auto-generated image description can be used as a starting point for writing alt text, but it should never be used for the final version without being reviewed and revised beforehand. Always edit auto-generated alt text for maximum accuracy.
Image accessibility features vary across third-party management tools and apps but most can access the alt text fields for Facebook, Twitter/X, and LinkedIn at the very least. Below is a sampling of different third-party management systems and SaaS companies and how they handle image accessibility.
Many third-party sites cannot access the alt text field for Instagram or Threads due to API restrictions. If you use a management system that cannot access the alt text field for those platforms, write your image description in the caption area of your post to make it accessible or schedule posts directly through the respective platforms.
If you're considering a third-party management system for your brand or organization, make sure to ask the following questions when connecting with a company's sales rep:
The below content was last updated on March 27, 2025.
The following social media management tools and apps can access Facebook's alt text field when scheduling posts:
The following social media management tools and apps can access Twitter/X's alt text field when scheduling posts:
The following social media management tools and apps can access Threads's alt text field when scheduling posts:
The following social media management tools and apps can access Instagram's alt text field when scheduling posts:
The following social media management tools and apps can access LinkedIn's alt text field when scheduling posts:
The following social media management tools and apps can access Pinterest's alt text field when scheduling posts:
Instructions on how to add image descriptions via specific management sites and apps (when available).
Want to learn a little more about alt text and image descriptions? Check out the links below!
