Guide
How to resize images correctly
Resizing changes an image's pixel dimensions: its width and height. It's how you fit a photo to a social media format, meet an upload requirement, or stop a huge camera photo from slowing down a web page. The Image Resizer uses high-quality smoothing and lets you pick the output format, so you can resize and save in one step.
Shrinking vs enlarging
Making an image smaller is safe: the resizer combines existing pixels and the result stays sharp. Making an image larger is different. The software has to create pixels that don't exist, so enlarged images look softer. Enlarging by up to about 1.5× is usually acceptable; beyond that, look for a larger original instead.
Aspect ratio
The aspect ratio is the shape of the image: 1:1 square, 16:9 widescreen, 4:5 portrait. Keep the lock on and the height updates automatically when you change the width, so the image never stretches. If you need a different shape, for example a landscape photo as a square Instagram post, unlocking will distort the picture, so crop it to the new shape first and then resize.
Sizes for common uses
- Instagram post: 1080 × 1080 (square) or 1080 × 1350 (portrait).
- Instagram or Facebook story: 1080 × 1920.
- YouTube thumbnail: 1280 × 720.
- Facebook cover: 820 × 312. X (Twitter) header: 1500 × 500. LinkedIn cover: 1584 × 396.
- Blog or website image: 1200–1600 pixels wide.
- Full-screen hero image: 1920 pixels wide.
Resizing for print
For printing, what matters is pixels per inch at the final size. Aim for 300 pixels per inch: multiply the print size in inches by 300. A 6 × 4 inch photo needs about 1800 × 1200 pixels; an A4 page needs about 2480 × 3508.
Choosing the output format
Save photos as JPG or WEBP with quality around 80–90%. Save graphics, screenshots and anything with transparency as PNG. All resizing happens in your browser, so your images are never uploaded.