Instagram post limits: caption length, image size and video length
Instagram is the strictest of the six networks about shape: an image outside 4:5 to 1.91:1 is refused, not cropped. It also needs media on every post — there is no text-only Instagram post.
Instagram limits at a glance
- Caption limit
- 2,200 characters
- Visible before “more”
- ~125 characters
- Image aspect ratio
- 4:5 to 1.91:1Refused outside this range
- At 1080 px wide
- 1080 × 1350 to 1080 × 565 px
- Minimum image width
- 320 px
- Video length
- 3 seconds to 1 min 30 s
- Most media per post
- 10Extras are dropped, not refused
- Text-only posts
- No — media required
- Hashtags
- Up to 30
- Mentions
- Up to 20
- Links clickable in text
- No
These are the limits for publishing through a scheduling tool — Instagram’s publishing API — and they are the same rules our editor checks as you write. Posting by hand in the Instagram app can allow a little more on some limits.
Planning an Instagram post
- Write the hook in the first ~125 characters. Everything after that sits behind “more”, and most people never tap it.
- Use 4:5 portrait (1080 × 1350 px) for single images — it takes up the most room in the feed.
- Links in captions are not clickable, so don’t spend caption space on a URL. Point people to the link in your bio instead.
- Instagram allows up to 30 hashtags, but a handful of relevant ones works better than a wall of them.
What an Instagram post can be
Through publishing, an Instagram post is one of three things: a single image, a carousel of up to 10 images and videos, or a single video published as a Reel. Every one of them needs media — Instagram has no text-only post to fall back on, so the creative has to exist before the post can be approved.
| Format | What it takes | Plan for |
|---|---|---|
| Single image | One image between 4:5 and 1.91:1 | 4:5 portrait, 1080 × 1350 px |
| Carousel | Up to 10 images or videos | One ratio for every slide |
| Reel | One video, 3 seconds to 1 min 30 s | Vertical 9:16, 1080 × 1920 px |
Publishing through a scheduling tool needs an Instagram professional account — Business or Creator. A personal account has to be switched first, which takes a minute in the Instagram app and doesn’t change anything followers see.
Refused, not cropped
Instagram is the one network that refuses an image for its shape. Anything taller than 4:5 or wider than 1.91:1 fails at publish time — after the client has approved it. That is why the shape is worth checking while the post is written, not when it goes out.
The rule applies to every slide of a carousel, not only the cover. A ten-slide carousel with one 9:16 image in the middle fails as a whole. Images must also be at least 320 px wide; anything exported for the web at a sensible size clears that easily.
Carousels and the profile grid
In the feed, every slide of a carousel is shown in the same frame, so design them all at one ratio — mixing a square cover with portrait slides gets the later slides cropped or letterboxed. Tell the story in order: the first slide has to earn the swipe, and the last one is where the call to action goes.
The profile grid shows each post as a portrait thumbnail cropped from the centre. Keep the subject and any text on the cover near the middle, or the grid will slice it.
Captions, hashtags, mentions and collaborators
Only the first ~125 characters of a caption show before “more”. The rest is there for people who are already interested — lead with the point, and put hashtags and credits at the end.
- Hashtags: up to 30. Go over and the post is refused, not trimmed
- Mentions: up to 20 @handles in a caption
- Links: not clickable in captions — point to the link in the profile instead
- Collaborators: a post can invite other accounts as co-authors, so it appears on their profile too once they accept
Many teams move hashtags into a first comment to keep the caption clean. A first comment can be posted automatically straight after the post goes live.