Resize for Instagram square posts (1080×1080)

Resize any image to 1080×1080 px for Instagram square posts. Free, no upload.

This preset makes a 1080 × 1080 square. Instagram's Help Center (checked 2026-09-28) says photos are shared up to 1080 px wide and kept at their resolution when the ratio is between 1.91:1 and 3:4; 1:1 is inside that range, so a 1080-px square is not resized or cropped again. Nerulio fills the square by cutting the centre out of your photo — from a 4032 × 3024 landscape that is the middle 3024 × 3024, a quarter of the width lost — or, with Fit inside, keeps the whole photo with margins.

Drop image files hereProcess many files at once

No upload · processed on this device

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What Instagram does with a square, and what the preset does

According to Instagram's help page, a photo narrower than 320 px is enlarged to 320, a wider one than 1080 is reduced to 1080, and a ratio outside 1.91:1–3:4 is cropped to a supported one. The page recommends uploading at least 1080 px wide. It does not name 1080 × 1080 as a required size; the square is simply one ratio Instagram keeps untouched.

The preset uses cover: the largest centred square is cut from the photo and scaled to 1080. From a landscape 4:3 photo, 504 px are removed on each side; from a portrait 3:4 photo, 504 px at the top and bottom. Fit inside keeps everything and adds bars instead. A source smaller than 1080 px is enlarged — Instagram would do the same, and neither adds detail.

1:1: Square; width equals height.
Cover (preset default): Fills the square and cuts the centred overflow.
Supported ratio range: 1.91:1 (wide) to 3:4 (tall) on Instagram's help page.

Square crops from two phone photos (computed from the code)

Example sources of 12 megapixels; the numbers follow the resize task's cover calculation.

Landscape 4032 x 3024 -> crop x 504..3528, full height = 3024 x 3024
                         scaled x 0.357 -> 1080 x 1080   (75 % of the photo kept)
Portrait  3024 x 4032 -> crop y 504..3528, full width  = 3024 x 3024
                         scaled x 0.357 -> 1080 x 1080   (75 % kept)

Fit inside instead (landscape): picture 1080 x 810, bars 135 px top and bottom

If the subject is not in the middle, pick the square yourself with crop (1:1 preset), then resize.

Check the result

The result list shows 1080×1080; the file name ends in -1080x1080.
Check the edges of the square: anything important near the left and right of a landscape photo is gone.
In Instagram's post preview the square should appear without a further crop.

Troubleshooting

Symptom	Likely cause	How to check	Fix
The subject is cut in half	Cover takes the centre; the subject was off-centre	Compare the square with the original	Crop the square yourself with crop, then resize
White bars in the post	Fit inside was chosen and the output is JPG	Output shows margins	Use the default fill, or pick a margin colour that suits the post
The post looks soft	The source was smaller than 1080 px and was enlarged	Source size in the result line	Use a larger original; enlarging adds no detail
I wanted the photo taller than square	A square is the shortest portrait ratio	—	Use the portrait preset instead

Other ways to do it

Option	When it is the better choice
Instagram portrait	Portrait photos: a 4:5 or 3:4 post shows more of the picture than a square.
Instagram's own crop when posting	You are posting from the phone and do not need a file: the app crops to a supported ratio itself.

What this page does not cover

The crop is always centred; there is no subject detection.
Instagram's own processing after upload (compression, feed display) is outside Nerulio's control.

Versions and sources

Instagram's behaviour is quoted from its Help Center page on photo resolution, read on 2026-09-28. The crop arithmetic follows src/task/resize.js and fitQuality() in src/image.js.

Official documentation used

Instagram Help Center: Image resolution of photos you share on Instagram

Resize for Instagram square posts (1080×1080)

Preset to 1080×1080 px (1:1). Photos with a different ratio are centre-cropped to fill the frame (cover); switch to contain to add margins instead.

Resampling uses the mks2013 filter of Pica. Platforms change their recommendations, so check their current guidance before posting.

Your file is never uploaded — it is processed inside this browser.

Example

Processed sample · 48 × 32

Example generated with this tool. ZIP tools show their preview; inspect the downloaded archive for every file.

Resize image

Set width and height, with optional aspect-ratio lock.

How it works

Open the source file
Choose the processing mode and settings
Run, inspect the result and download

Supported formats

PNG / JPG / WebP / AVIF / HEIC → PNG — Input decoding and output encoding depend on browser support. Animated inputs are rejected; select a still frame first.

What this tool does

Tiled high-quality mks2013/Lanczos resampling, numeric dimensions and size helpers.

Implementation and verified quality

advanced · Pica tiled mks2013 / Lanczos. Quality qualification is in progress. Pro/Flagship quality has not been established.

Before you export

Actual device memory, storage and codec support. Tested examples are evidence, not a guarantee for every file.

Frequently asked questions

What determines the supported size?

Actual device memory, storage and codec support. Tested examples are evidence, not a guarantee for every file.

Are my files uploaded?

This tool processes the files you open on your device without uploading them. Images you explicitly attach to community posts are uploaded separately. Optional engines and models are downloaded from third parties; those requests expose connection information such as your IP address.

Will my work be saved automatically?

No. Images and editing state stay in this tab; media output can use local temporary storage. Changing language preserves your work; reloading, closing the tab, or following a link to another page can clear it.