Every platform wants a different image size: 1080 × 1080 for an Instagram post, 1280 × 720 for a YouTube thumbnail, 600 × 600 for a job portal photo. Resizing an image changes its width and height in pixels. Done right, it looks sharp; done wrong, it looks stretched or blurry. This guide explains how to resize an image properly with our free Image Resizer.
Pixels and aspect ratio
An image’s size is its width × height in pixels. The aspect ratio is the relationship between them, such as 4:3 or 16:9. If you change width and height by different proportions, the image stretches.
Resize by pixels
- Open the image resizer and choose your photo.
- Turn on “keep aspect ratio”.
- Type the width you need; the height adjusts automatically.
- Download.
Resize by percentage
Choose 50% to halve both width and height. A 4000 × 3000 photo becomes 2000 × 1500. The file size usually drops to about a quarter.
When you need exact width and height
If a form demands exactly 600 × 600 px but your photo is 4:3, resizing will stretch it. Crop to a square first with the Image Cropper, then resize to 600 × 600.
Making images bigger
Enlarging a small image cannot add real detail; it becomes soft or blurry. Start from the largest original you have.
Common sizes
| Use | Size (px) |
|---|---|
| Instagram square post | 1080 × 1080 |
| Instagram portrait | 1080 × 1350 |
| Story / status | 1080 × 1920 |
| YouTube thumbnail | 1280 × 720 |
| Facebook cover | 851 × 315 (desktop display) |
| Profile photo | 400 × 400 |
Platforms change recommendations from time to time. Read social media image sizes for more.
Resize, then compress
After resizing, compressing reduces the file size further without changing dimensions; use the Image Compressor.
DPI and printing
For printing, pixels per inch matter. A 6 × 4 inch print at 300 DPI needs 1800 × 1200 pixels. On screens, DPI settings in the file do not change how big the image appears; pixels do.
Frequently asked questions
How do I resize an image without stretching it?
Keep the aspect ratio locked, or crop to the target ratio first.
Does resizing reduce file size?
Yes, making an image smaller in pixels usually reduces the file size a lot.
Can I make a small image bigger without blur?
Not really; enlarging cannot add detail that was not captured.