Instagram’s feed accepts anything between 1.91:1 landscape and 4:5 portrait. Export 1080 x 1350 for 4:5, 1080 x 1080 for square, 1080 x 566 for landscape and 1080 x 1920 for Reels and Stories. Outside that window the feed trims your image. This checker reads the real pixel dimensions of your file and shows exactly what would be cut.
What happens to your file between export and feed
Most people find out their photo was the wrong size after it is already published and the top of someone’s head is missing. The checker exists to move that discovery earlier, so it helps to know what the upload pipeline is doing.
Aspect ratio is enforced first. The feed has a hard window: no wider than 1.91:1, no taller than 4:5. A ratio inside that window posts without a forced crop. A ratio outside it gets trimmed to the nearest edge of the window before anything else happens. Taller than 4:5 loses height off the top and bottom; wider than 1.91:1 loses width off the left and right. The tool computes the exact pixel loss for your file and flags anything above 35% as a heavy crop, because at that point you are not posting the photo you took.
Then it is resized. Anything wider than 1080 px is scaled down to 1080. This is why a 6000 px export is not an investment in quality — it is an extra resampling pass you have handed to a stranger’s encoder. Matching 1080 px on the long-ish edge yourself, in software you control, is the single biggest lever you have.
Then it is re-compressed. Instagram re-encodes uploads. The specific parameters are not published anywhere by Meta, they differ between the app and the web uploader, and they have visibly changed over the years, so any exact quality number you see quoted is somebody’s guess. What is consistently observable is which content suffers: smooth gradients band, small text goes mushy, and heavy grain or noise eats the bit budget that should have gone to your subject.
Why 4:5 takes the most vertical space
The feed renders every post at the same column width, then derives height from the ratio. At 4:5 the height is 1.25 times the width, which is the tallest the feed allows. Square is 1.0 times the width. A 1.91:1 landscape is only about 0.52 times the width — roughly two-fifths the screen height of a 4:5 post from the same account. That is pure geometry. Whether more screen area translates into more reach is a claim about ranking that Instagram has not published, and you should treat confident assertions about it as unverified.
Instagram size specifications
| Surface | Export size | Ratio | Decimal (w/h) | Notes |
|---|---|---|---|---|
| Feed, portrait | 1080 x 1350 px | 4:5 | 0.800 | Tallest the feed accepts. Most vertical screen space per post. |
| Feed, square | 1080 x 1080 px | 1:1 | 1.000 | Posts untouched. Also the shape a profile photo is cropped to. |
| Feed, landscape | 1080 x 566 px | 1.91:1 | 1.910 | Widest the feed accepts. 1080 / 1.91 rounds to 566 px. |
| Reels and Stories | 1080 x 1920 px | 9:16 | 0.5625 | Full-screen vertical. Nothing is cropped horizontally at this ratio. |
| Profile photo | 1080 x 1080 px | 1:1 | 1.000 | Displayed as a circle, so keep the subject well inside the corners. |
The checker matches a file to 9:16 within a tolerance of 0.02 on the decimal ratio, and treats 1:1 as exact within 0.005. Those tolerances exist because real exports are rarely mathematically perfect — a 1079 x 1349 file is a 4:5 file for every practical purpose.
Reading the crop preview
Drop an image and the right-hand panel draws your photo with the target crop rectangle laid over it, dimmed outside and rule-of-thirds guides inside. The two focal-point sliders move that rectangle horizontally and vertically as a percentage of the leftover space, so 50/50 is a plain centre crop and 0/0 pins the crop to the top-left corner.
Underneath you get the numbers that matter: the crop rectangle in source pixels with its origin, the percentage of pixels discarded, and the output size it would export to. The download button writes that crop as a PNG at the exact target dimensions, resampled once with high-quality smoothing. That file is ready to upload with no further editing.
Getting this right before you export
- Set the document size at the start. 1080 x 1350 or 1080 x 1920 as a canvas is a decision that costs nothing on day one and cannot be undone cheaply on day thirty.
- Shoot looser than you need. If you know the final frame is 4:5 but you are shooting 3:2 or 16:9, leave headroom. A crop you planned is free; a crop the feed imposes is not.
- Check before you publish, not after. Drop the finished export here, read the verdict, and if it says the feed will trim it, fix the export rather than accepting the trim.
- Do not upscale to hit 1080. A 720 px wide source stretched to 1080 is softer than the same source at 720. Instagram will handle the scaling either way; you gain nothing by doing it badly first.
- Export video vertically from the timeline. Re-cropping a finished 16:9 export to 9:16 throws away most of the frame. Set the sequence to 1080 x 1920 before you start editing, and frame for it.
Video: length, ratio, and what this tool will not do
Drop a video and the checker reports its true track dimensions, aspect ratio, duration, orientation and file size, and tells you how it would behave in a 9:16 Reel. A 0.5625 ratio fits full screen with nothing cropped horizontally. Narrower than that and the top and bottom are trimmed. Wider and Reels either pillarboxes it or crops the sides — the tool computes the percentage of width you would lose. A true landscape clip is flagged as a poor fit, because it is: at 16:9 you lose roughly 68% of the width to a 9:16 frame.
On duration, the tool uses 90 seconds as the common Reel cap and 180 seconds as the longer ceiling available on many accounts, and notes that Story segments split every 60 seconds. Treat those as current-behaviour figures rather than fixed law. Instagram has changed maximum Reel length more than once, and the limit has differed between accounts and regions during rollouts. If your clip is near a boundary, verify in the app.
The honest limits
This tool reads video metadata only. It hands the file to your browser’s own decoder, waits for the loadedmetadata event, and reports the width, height and duration the decoder found. That is the whole of it. It does not transcode, re-encode, resize, trim, rotate or compress your video, and it never will — a browser tab is the wrong place to run a video pipeline. For an actual re-crop or a re-encode, use a video editor. The image side does produce a real cropped PNG, but the video side is measurement only.
Codec support is your browser’s, not ours. If your browser cannot decode the file, the tool cannot read it. A 15-second timeout catches files that stall, and the error tells you to try an MP4 with H.264, which is the most broadly decodable combination. Some MOV and MKV files, and anything with an exotic codec, will simply refuse to report metadata. An audio-only file reports no video track.
Duration can be missing. Some containers and some fragmented streams report an infinite or absent duration to the browser. When that happens the tool says the duration is unknown rather than inventing one.
Practical ceilings. Images up to 100 MB and roughly 80 megapixels; anything larger is refused rather than risking the tab. Large videos take a moment because the browser has to fetch enough of the file to find the metadata atom. Exported crops are PNG, which is lossless but large — that is deliberate, so the only lossy step in the chain is the one Instagram applies.
The feed window is Instagram’s, not ours. If Meta widens or narrows the accepted ratio range, this page and the tool will be out of date until they are updated. The numbers here describe behaviour that has been stable for a long time, not a contract.
This runs in your browser
No sign-in, no Instagram password, no account connection. Images you open here are read by your own browser with the Canvas API from a local object URL. There is no upload endpoint on this site, so there is nowhere for the file to go. Open your browser’s network tab and watch: after the page loads, there are no further requests.
Frequently asked questions
What size should Instagram photos be?
1080 px on the width, with the height set by your ratio: 1080 x 1350 for 4:5 portrait, 1080 x 1080 for square, 1080 x 566 for 1.91:1 landscape, and 1080 x 1920 for Reels and Stories.
What is the tallest photo Instagram allows in the feed?
4:5, a decimal ratio of 0.800, which is 1080 x 1350 px. Anything taller is trimmed at the top and bottom to fit. The checker tells you how many pixels would be lost on your specific file.
What size should a Reel or Story be?
1080 x 1920 px, a 9:16 ratio of 0.5625. At that exact ratio nothing is cropped horizontally, though Instagram still draws its own buttons and captions on top of your frame.
Does this tool resize or convert my video?
No. It reads video metadata only — width, height and duration straight from your browser’s decoder. It does not transcode, trim, re-encode or resize anything. Use a video editor for the actual re-crop. Images are different: the tool can export a real cropped PNG.
Why does my portrait photo get cropped in the feed?
Because it is taller than 4:5. The feed window stops at a 0.800 ratio, so a 9:16 or 2:3 photo has its top and bottom trimmed. Crop it to 4:5 yourself and you control which part survives.
Should I export bigger than 1080 px for better quality?
No. Uploads wider than 1080 px are scaled down anyway, so a larger export just adds a resampling pass you did not control. Export at exactly 1080 px wide from your own software.
How long can a Reel be?
The tool flags anything over 90 seconds as beyond the common cap and anything over 3 minutes as beyond the longer ceiling many accounts have. These limits have changed more than once and vary during rollouts, so check the app if your clip is near a boundary. Story segments split every 60 seconds.