How to use the Social Media Image Resizer
- Choose your image. Pick a file or drop it on the box. It is read by your browser only.
- Pick a network and placement. For example Instagram feed portrait, X header or a Bluesky profile photo. The exact pixel size is shown.
- Choose fit or fill. Fill crops to cover the whole frame and lets you slide the crop. Fit keeps the whole image and adds bars in a colour you choose.
- Download. Pick PNG or JPG and download a file at exactly the preset size.
How the image resizer works
Method
Fill picks the larger of the two scale factors, width ratio or height ratio, so the picture covers the frame, then crops the overflow around the crop position you set. Fit picks the smaller scale factor so the whole image is visible, and centers it on a background rectangle.
The export is a canvas of exactly the preset width and height. Scaling uses the browser's high quality smoothing. Photos are never enlarged beyond what the preset needs, but a small source stretched to a large preset will look soft.
Where the sizes come from
Presets cover each network TimeToPost publishes to. They are the widely used recommended dimensions for each placement. No network guarantees an exact size, because each one recompresses uploads, and the guidance changes over time. The Social Media Image Sizes guide on the blog explains the common ratios.
Privacy and limits
Everything happens locally. The tool does not read or keep EXIF location data in the exported file, because a canvas export contains pixels only. Animated GIFs export as a still image of the first frame.
Frequently asked questions
What size should an Instagram image be?
A common target for a feed portrait is 1080 x 1350 pixels (4:5), a square is 1080 x 1080, and Stories and Reels covers are 1080 x 1920 (9:16). The presets here use those sizes.
Are these sizes official rules?
They are the commonly recommended source sizes. Networks re-compress and sometimes re-crop on upload, and their guidance changes, so treat each preset as a safe target and check the preview in the app before publishing.
Is my image uploaded?
No. The image is drawn on a canvas inside your browser and the file you download is made on your device.
What is the difference between fit and fill?
Fill scales the image until it covers the frame and crops the overflow, so nothing is left empty. Fit scales it down until all of it is visible and fills the leftover space with your background colour.
Should I download PNG or JPG?
PNG is lossless and best for graphics and text. JPG makes a smaller file for photos, which helps on networks with file size caps. JPG has no transparency, so any empty area takes your background colour.
Why does a very large photo take a moment?
The browser has to decode the full image before scaling it. Very large files can take a second or two on a phone. Nothing is waiting on a server.