Drop an image here, or
Processed in your browser. The file is never uploaded.
Add an image to see the resized preview.
Why the right dimensions matter
Upload the wrong ratio and the platform crops it for you, usually badly and usually through the part you cared about. Text gets cut off, faces get halved, and a thumbnail that looked deliberate in your editor looks careless in the feed.
Getting it right also protects quality. Platforms re-compress anything that does not match their expected size, and re-compression is where sharpness goes.
Crop to fill, or fit the whole image?
- Crop to fill covers the frame completely with no bars, at the cost of trimming the edges. Right for photos and almost always right for feed posts.
- Fit whole image keeps everything visible and pads with white. Right when the edges carry information, text, diagrams, screenshots, product shots where the whole object matters.
Common sizes worth remembering
- Instagram portrait post, 1080×1350
- Instagram story / reel, 1080×1920
- YouTube thumbnail, 1280×720
- X post image, 1600×900
- LinkedIn post, 1200×627
- Link preview / Open Graph, 1200×630
Design for the small version
Almost nobody sees your image at full size. A thumbnail is often rendered a few hundred pixels wide on a phone. Before you publish, shrink the preview until it is that size: if the subject is not instantly readable, the composition needs to be simpler, not the resolution higher.
Nothing leaves your device
Most free resizers upload your file to a server, process it there and hand back a link, which means your unreleased content sits on someone else's infrastructure under whatever terms they wrote. This tool uses a canvas element in your own browser. Turn off your connection after the page loads and it still works.
Frequently asked questions
- What size should an Instagram post be?
- 1080×1080 for a square, 1080×1350 for portrait, and 1080×1920 for stories and reels. Portrait takes up the most vertical space in the feed, which is why most creators default to it.
- What size is a YouTube thumbnail?
- 1280×720 pixels, a 16:9 ratio, under 2MB. Design it so the subject still reads at roughly 210 pixels wide, because that is closer to the size most viewers actually see it at.
- Are my images uploaded to a server?
- No. The resizing happens on a canvas inside your browser using JavaScript. The file never leaves your device, which means unpublished content stays private and the tool works the same whether your connection is fast or slow.
- Why does my image look blurry after resizing?
- Because the source was smaller than the target, so it had to be upscaled, enlarging an image cannot add detail that was not captured. The tool warns you when this will happen. Start from the largest original you have.
Get paid while you grow
These tools are free and always will be. If you want to go further, 4lo4lo pays you points for completing social tasks, teaches growth in the Classroom, and gives you a public profile you can put in your bio.