Social Media Image Resizer

What it does

Instantly resizes and crops an image to match the exact dimensions required by popular social media platforms — Instagram posts and stories, Facebook covers, Twitter/X posts, LinkedIn banners, YouTube thumbnails, and more. Everything happens in your browser using the HTML5 Canvas API: your image is never uploaded anywhere.

Unlike a simple auto-crop, this tool shows an interactive preview where you can drag the image to reposition it and use a zoom slider to fine-tune exactly which part of the picture ends up in the final crop, before exporting.

Try it

How it works

1. You pick an image file — it's loaded locally into an <img> element using URL.createObjectURL(); the file never leaves your device.
2. When Fit mode = Cover, an interactive editor appears: a preview frame at the target format's aspect ratio, with your image drawn inside it, scaled just large enough to always fully cover the frame.

• Drag the image with your mouse (or finger, on touch devices) to pan it and choose exactly which part is kept.
• Use the Zoom slider to scale the image up further, letting you crop in tighter on a specific detail.
• Reset position re-centers the image and resets the zoom.

1. When you click Convert, a <canvas> is created at the exact target pixel dimensions, and the same pan/zoom transform you set up in the editor is reproduced at full resolution — so what you see in the editor is exactly what you get, at the target size.
2. Contain and Stretch modes don't need manual positioning (the whole image is always kept), so the editor is hidden for those modes.
3. The canvas is exported with canvas.toBlob() in your chosen format (PNG, JPEG, or WebP) and quality, and offered as a downloadable file via an object URL.

Supported formats

Notes

• Nothing is uploaded: the entire pan/zoom/crop/export pipeline runs locally in your browser via the Canvas API.
• PNG output is lossless but larger; JPEG/WebP let you tune quality vs. file size with the quality slider.
• Switching the target format or custom size resets the crop position and zoom, since the frame's aspect ratio changes.
• For best results, choose a source image with a resolution equal to or larger than the target format to avoid visible upscaling when you zoom in.