Resize a photo for Instagram
What this tool does
This page starts on the portrait post preset, the shape that takes the most vertical space in a feed. The preset list holds the square, landscape and story sizes too.
Pre-set for you: Portrait post preset (1080 × 1350 px). You can change it before you drop a file.
This browser cannot resize images locally. It needs Web Workers with OffscreenCanvas support, and we will not fall back to resizing on the main thread because that would freeze the page. Please try a current version of Chrome, Edge, Firefox or Safari.
How this works
The resize happens inside a Web Worker in this browser tab, using a Lanczos-style resampling filter, so edges stay smooth instead of going jaggy the way a cheap nearest-neighbour scale does. The image never reaches a server.
- Preset sizes are real platform values, and each one is documented in the source with where it came from — YouTube asks for 3840×2160 for video thumbnails, for instance, not the 1280×720 people often repeat.
- With the aspect ratio locked, the image scales to fit inside the box you type, so nothing is stretched. Unlock it to set an exact width and height.
- Small images are left alone unless you tick Allow enlarging: interpolation can add pixels but not detail.
- A batch resizes every image to the same box, then comes back as a single ZIP.
- Nothing is stored: reloading the page discards everything.
Portrait images get more room in a feed than landscape ones do, up to a 4:5 ratio, which is why 1080 × 1350 is the shape most people settle on for a feed post. This page opens with the portrait preset selected, so the box is already 1080 × 1350 before you drop anything. The square, landscape, story and reel presets are one click away in the same list.
As with every resize here, that is a box rather than a forced shape. Your image is reduced until it fits inside 1080 × 1350 with its proportions intact. A 3:2 camera file lands at 1080 × 720; a 4:3 phone photo lands at 1080 × 810. Nothing is stretched, and nothing is cropped.
Worth knowing before you choose a preset, because these limits are about what survives being shown:
- Landscape wider than about 1.91 to 1 loses its outer edges in the feed, even though the file itself is untouched. The landscape preset stops at that ratio for exactly this reason.
- Portrait taller than 4:5 gets trimmed at the top and bottom in the feed, which is why the portrait preset stops at 4:5 rather than going all the way to 9:16.
- Stories and reels are a separate, full-screen format at 9:16, and they have their own preset. Using the feed portrait size for a story leaves bars at the top and bottom.
On where the numbers come from: the platform publishes aspect-ratio limits rather than a table of pixel sizes, so the preset records that its dimensions are derived from those published ratios instead of being quoted back as official. Pick a preset and the note under the controls prints its exact size, its ratio and that source line, so nothing here is a number you have to take on trust.
If you need the picture to fill the tallest feed slot exactly, resizing alone will not do it — your photo fits inside the box with room to spare. Crop to 4:5 first so the whole frame is used, then resize to 1080 × 1350 for a file that fills the space with nothing trimmed by the feed.
Frequently asked questions
Which size should I use for a feed post?
Portrait at 1080 × 1350 if the photo suits it, because portrait takes the most vertical space. The square preset is the safe choice for anything that has to work in a grid.
Will resizing crop my photo to fit?
No. Resizing fits the image inside the chosen box and keeps its proportions, so nothing is removed. If you want the frame filled completely, crop to the ratio first.
Why does the preset say its size is derived?
Because the platform publishes ratio limits, not pixel tables. The dimensions are arithmetic on those published limits, and the preset says so rather than implying an official figure was quoted.
Do these presets cover stories and reels?
Yes — there is a separate 9:16 preset for full-screen vertical formats, alongside the feed portrait one.
Resize Image with different settings
Set a width, a height, or both, and the image is rescaled inside your browser tab. Aspect ratio stays locked unless you unlock it, and the file never leaves your device.