Image Resizer Online
Resize images to exact dimensions for any use case—social media, websites, email, print, or any specific size requirement. This free online tool lets you scale images up or down while maintaining quality and offers both exact pixel dimensions and percentage-based scaling.
Understanding Image Resizing
Resizing changes the pixel dimensions of an image. Downscaling (making smaller) generally maintains quality well because existing pixels are sampled. Upscaling (making larger) can reduce quality because new pixels must be interpolated from existing ones. For best results, always start with the largest available original and resize down.
Social Media Image Sizes
| Platform | Post Type | Dimensions | Aspect Ratio |
|---|---|---|---|
| Feed post | 1200 x 630 | 1.91:1 | |
| Story | 1080 x 1920 | 9:16 | |
| Square | 1080 x 1080 | 1:1 | |
| Portrait | 1080 x 1350 | 4:5 | |
| Landscape | 1080 x 566 | 1.91:1 | |
| Story/Reel | 1080 x 1920 | 9:16 | |
| Twitter/X | In-stream | 1200 x 675 | 16:9 |
| Post | 1200 x 627 | 1.91:1 | |
| Pin | 1000 x 1500 | 2:3 | |
| YouTube | Thumbnail | 1280 x 720 | 16:9 |
Website Image Sizes
| Use Case | Recommended Width | Notes |
|---|---|---|
| Hero/Banner | 1920px | Full-width, above fold |
| Blog content | 800-1200px | Within article body |
| Sidebar | 300-400px | Sidebars, widgets |
| Thumbnails | 300-400px | Galleries, cards |
| Product images | 800-1200px | E-commerce detail |
| Avatars | 100-200px | User profiles |
| OG images | 1200 x 630 | Social sharing |
Retina/HiDPI Considerations
Modern devices have high pixel density displays (2x, 3x). To appear sharp:
| Display Size | @1x | @2x (Retina) | @3x |
|---|---|---|---|
| 100px display | 100px | 200px | 300px |
| 400px display | 400px | 800px | 1200px |
| 800px display | 800px | 1600px | 2400px |
css
img {
width: 400px;
height: auto;
}
``Aspect Ratio Guide
| Ratio | Common Uses | Example Sizes |
|---|---|---|
| 1:1 | Instagram, avatars | 1080x1080, 500x500 |
| 4:3 | Traditional photos | 1200x900, 800x600 |
| 3:2 | DSLR photos | 1200x800, 900x600 |
| 16:9 | YouTube, HD video | 1920x1080, 1280x720 |
| 9:16 | Stories, vertical video | 1080x1920 |
| 2:3 | Pinterest pins | 1000x1500 |
Quality Preservation Tips
1. Always resize down, not up - Start with the largest original 2. Resize before compression - Reduces pixel count first, then compress 3. Maintain aspect ratio - Avoid stretching or squishing 4. Use appropriate algorithm - Lanczos for photos, nearest-neighbor for pixel art 5. Save in correct format - JPEG for photos, PNG for graphics
Use this resizer to prepare images for any platform or use case with precise dimension control.