Image Resizer

It depends on where the image will be used. Common sizes: 1200x630 for social media share images (Facebook, LinkedIn), 1080x1080 for Instagram square posts, 1080x1350 for Instagram portrait (best engagement), 1280x720 for YouTube thumbnails, and 1920x1080 for presentations. For email images, keep width under 600px.

Upscaling beyond 150-200% of the original size usually produces noticeable blur or pixelation. The browser uses bilinear interpolation which smooths but cannot invent real detail. For best results, always start with the largest source image available and scale down.

Yes. Without it, your image will stretch and distort. Keep it locked when resizing for display. Only unlock it when you need an exact non-proportional size, like fitting a landscape photo into a square.

Browser canvas limits vary: Chrome supports up to ~16,384x16,384 pixels, Firefox up to ~21,744x21,744, but Safari is more limited at ~4,096x4,096. Very large images may be slow to process on mobile devices.