Last updated: October 2026
How many images can a LinkedIn post have?
Through LinkedIn's API a multi-image post holds 2 to 20 images (JPG, PNG or GIF, each under about 36 megapixels), and each image can carry alt text up to 4,086 characters. A swipeable carousel is a different format: a PDF document post.
How many images can a LinkedIn post have depends on which kind of post you mean. LinkedIn has single image posts, multi-image posts, document posts that people call carousels, and a carousel ad format. Each has its own rules, and the numbers that get repeated online often mix them up.
The limits below come from LinkedIn's API documentation and LinkedIn Help. One honest gap: we could not find a LinkedIn Help page that states how many images LinkedIn's own composer accepts, so the in-app cap may be lower than the API's 20.
Multi-image post vs carousel vs document post
These are four different content types. If you want readers to swipe through slides, you want a document post, not a multi-image post.
Multi-image post. LinkedIn's MultiImage API page says a multi-image post contains a minimum of 2 and a maximum of 20 images, and that API partners can only create non-sponsored multi-image posts. It works for a personal profile with the self-serve w_member_social scope.
Document post. This is the "LinkedIn carousel" most people mean: a PDF (or PPT, PPTX, DOC, DOCX) where every page becomes a slide. LinkedIn caps documents at 100 MB and 300 pages. Full details in can you post a LinkedIn PDF carousel via the API. To design the slides, try the LinkedIn carousel generator.
Carousel content type. LinkedIn's Posts API lists a separate carousel type made of image cards, each with its own landing page. It is marked sponsored only, with the note "Organic carousel is currently not supported." That is an ad, not something you post to your feed.
LinkedIn image limits: count, formats and pixels
From LinkedIn's MultiImage API and Images API pages (version 202609) and LinkedIn Help.
The API is stricter on formats than the LinkedIn app: HEIC and WEBP files are listed for the app but not for the Images API, so convert them to JPG or PNG before uploading through code. For recommended dimensions, see the LinkedIn image size guide, and check how the post will look with the LinkedIn post preview.
LinkedIn alt text character limit
LinkedIn's API documentation gives the altText field a maximum of 4,086 characters and recommends keeping it under 120. The recommendation is the number to aim for: screen readers read alt text in full, and one clear sentence about what the image shows is easier to follow than a paragraph.
In a multi-image post, each image gets its own alt text. LinkedIn's sample request puts altText next to each image URN:
"content": {
"multiImage": {
"images": [
{ "id": "urn:li:image:C4D22AQFttWMAaIqHaa", "altText": "Bar chart of weekly signups" },
{ "id": "urn:li:image:C4D22AQG7uz0yPJh588", "altText": "Team photo at the launch event" }
]
}
}Each image URN comes from its own initializeUpload call on /rest/images followed by an upload of the file, so a 20-image post means 20 initialize calls, 20 uploads and then the post itself. Need help writing the descriptions? The alt text generator drafts short alt text from an image.
What OpenTweet supports today
OpenTweet publishes to your personal LinkedIn profile through LinkedIn's own API. From the composer you can attach up to 4 images per post. One image goes out as a single image post, two or more go out as a LinkedIn multi-image post. The same post can go to X and Bluesky at the same time.
What it does not do yet
OpenTweet does not send alt text to LinkedIn, does not post PDF document carousels, and does not post video to LinkedIn. If you need any of those today, post from the LinkedIn app or call the API yourself.7-day free trial. Cancel anytime.
Frequently asked questions
How many images can a LinkedIn post have?
Through LinkedIn's API, a multi-image post holds a minimum of 2 and a maximum of 20 images, per LinkedIn's MultiImage API page. A single image post holds one. We could not find a LinkedIn Help page that states the cap in LinkedIn's own app, so the number you see when posting from linkedin.com may differ.
What is the difference between a LinkedIn multi-image post and a carousel?
A multi-image post shows 2 to 20 separate images in a grid. What most people call a LinkedIn carousel is a document post: a PDF whose pages readers swipe through. LinkedIn also has a carousel content type built from image cards, but its Posts API lists that one as sponsored only, so it is an ad format.
What is the LinkedIn alt text character limit?
LinkedIn's API documentation gives a maximum of 4,086 characters for image alt text and recommends keeping it under 120 characters. Short, specific alt text that says what is in the image works best for screen reader users.
Which image formats does LinkedIn accept?
The LinkedIn Images API accepts JPG, PNG and GIF, with images under 36,152,320 pixels and GIFs up to 250 frames. LinkedIn's help page on media types lists GIF, HEIF/HEIC, JPEG, PNG and WEBP for images shared in the app, with a maximum of 36 megapixels.
Can I add alt text to every image in a multi-image post?
Yes. In the API request each entry in the multiImage images array can carry its own altText field next to the image URN, as shown in LinkedIn's own sample request.
How many images can OpenTweet post to LinkedIn?
Up to 4 images per post from the OpenTweet composer. One image publishes as a single image post, two or more publish as a LinkedIn multi-image post. OpenTweet does not send alt text to LinkedIn yet, and it does not post PDF document carousels or video to LinkedIn. Plans start at $11.99 a month with a 7-day free trial.
Sources: Microsoft Learn LinkedIn docs for the MultiImage API, Images API, Posts API and Documents API (version 202609), and LinkedIn Help on media file types supported on LinkedIn. Checked 10 October 2026.
Keep exploring
LinkedIn images, carousels and previews.
LinkedIn image size guide
Every LinkedIn image size with its source, plus a crop preview.
LinkedIn post preview
See how your post text and images will look in the feed.
LinkedIn carousel generator
Turn an idea into PDF carousel slides you can upload.
Can you post a PDF carousel via the API?
Yes. The 3-step Documents API flow and its limits.
Alt text generator
Write short, specific alt text for any image.
LinkedIn scheduler
Schedule LinkedIn text and image posts next to X and Bluesky.
Schedule image posts to LinkedIn and X
Write once, attach up to 4 images, and publish to LinkedIn, X and Bluesky from one composer, from $11.99 a month.
7-day free trial. Cancel anytime.