Free to try · Instagram post resizer
Resize videos for Instagram posts in 4:5 or square
A feed post can be portrait 4:5 or square 1:1, and landscape video looks small in both.
Cropus crops your video to the shape you pick and follows the subject, so the post fills the screen without cutting anyone off.
- Smart crop follows your subject — no keyframes
- 9:16, 4:5, 1:1 and 16:9 from one upload
- No watermark, original sound
5 free minutes · No card needed
Why Cropus
Feed posts that fill the screen
Portrait 4:5 for more screen
4:5 is the standard portrait feed shape — taller than square, so your video covers more of the scroll.
Square 1:1 for cross-posting
Square works on Instagram, Facebook and LinkedIn alike, so one file covers several feeds.
Products stay centered
Hands, products and models move; the crop moves with them, smoothly.
Get the Reel too
Add 9:16 to the same upload for Reels and Stories. Extra formats are free.
Center crop vs Smart crop
The crop that keeps up
A plain center crop cuts whatever happens to be in the middle. Smart crop tracks the subject through the shot, so the action never leaves the screen.
Smooth camera
The crop glides with your subject. No jitter, no seasick jumps between frames.
Cuts handled
On a scene cut the frame jumps cleanly to the new shot instead of panning across it.
Blur fill
Balanced and Fit fill the bars with a soft, blurred copy of your video — or classic black.
Every format at once
Pick every aspect ratio together. One analysis powers them all, so extra formats are quick and free.
How it works
From one upload to every feed
Upload your video
Drop in any clip — a vlog, a dance, a match highlight, a product shot. Landscape or portrait, up to 4 GB.
AI finds and follows the subject
Cropus watches every scene, finds who matters and plans a smooth camera path that keeps them in frame.
Download every format
Get 9:16, 4:5, 1:1 and 16:9 versions from one upload — ready for Shorts, Reels, TikTok and feeds.
FAQ
Frequently asked questions
What size is an Instagram portrait video post?
4:5 at 1080×1350 pixels is the standard portrait size. Square posts are 1:1 at 1080×1080.
Is 4:5 or 1:1 better for Instagram video?
4:5 takes more vertical space in the feed, which helps it stand out while people scroll. 1:1 is the safer pick when the same file also goes to other platforms.
How do I post a landscape video on Instagram without it looking tiny?
Reframe it to 4:5. Cropus crops the landscape frame to portrait and follows the subject, so the post fills the width of the phone and the action stays visible.
Can I make the 4:5 and square versions at once?
Yes — both are selected in the form above. One upload, one charge, two files.
What if my subject is near the edge of the frame?
Smart crop finds the subject wherever it is and places the frame around it, instead of taking the center of the picture.
Do I need an app to resize Instagram videos?
No. Cropus runs in your browser on desktop or phone. Upload, choose the sizes, download the MP4s and post them from the Instagram app.
More tools
Other ways to reframe
Try it on your own video
Resize videos for Instagram feed posts in 4:5 portrait or 1:1 square. Cropus keeps the subject in frame automatically. Start with 5 free minutes.
Reframe a video5 free minutes · No card needed