Image Resizer — Change Image Dimensions Online
Change the width and height of any picture in seconds. Enter exact pixels or a percentage, lock the aspect ratio so nothing gets stretched, or pick a ready-made preset for Instagram, YouTube, Facebook and more. Your images are resized privately in your browser.
How to use the Image Resizer
- Add one or more JPG, PNG or WebP images.
- Type a new width or height, choose a percentage, or tap a preset size. Keep the lock on to preserve the proportions.
- Pick an output format and, for JPG or WebP, a quality level.
- Press Resize, check the previews and download your images individually or as a ZIP.
Keeping the right proportions
The aspect ratio is the relationship between width and height. When the lock is on, changing one number automatically updates the other so the picture is never squashed or stretched. Turn the lock off only when you need an exact size that has a different shape from the original.
When a preset has a different shape from your photo, choose “Crop to fill” to cover the whole frame by trimming the edges, or “Stretch” to force the exact size.
Choosing the right size
For websites, an image rarely needs to be wider than 1600 pixels. For social posts, use the exact dimensions the platform recommends to avoid automatic cropping. For print, aim for the physical size multiplied by 300 pixels per inch — a 6 × 4 inch photo should be about 1800 × 1200 pixels.
Ideas & examples
- Instagram post: Pick the 1080 × 1080 preset with “Crop to fill” to turn any photo into a perfect square.
- YouTube thumbnail: Use the 1280 × 720 preset so your thumbnail is sharp and never letterboxed.
- Halve a large photo: Switch to percentage mode, enter 50 and your 4000 px photo becomes 2000 px — ideal for email and blogs.
Frequently asked questions
Can I resize an image without losing quality?
Making an image smaller keeps it sharp. Making it larger cannot add real detail, so enlarged pictures can look soft. Start from the largest original you have.
How do I keep the aspect ratio?
Leave the lock switched on. When you change the width, the height follows automatically, and the other way round.
Does the tool upload my photos?
No. Resizing happens in your browser. Nothing is sent to us or anyone else.
Which formats are supported?
You can upload JPG, PNG and WebP images and download the result as JPG, PNG or WebP.
Is there a limit on image size?
Each image can be up to 25 MB, up to 30 images at a time. Output dimensions can be up to 8000 pixels on either side.
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