Need a fast image resizer? Use the free tool above to change image dimensions, shrink a photo to a target KB size, convert between JPG, PNG and WebP, and download the result without installing anything.
What Is an Image Resizer?
An image resizer changes the width and height of a picture and saves a new copy at the dimensions you choose. A phone photo can be 4000 pixels wide, while a blog card, profile picture or online form may need only a few hundred. Resizing gives you a version that fits the space, loads faster and is easier to share.
This tool runs entirely in your browser. You pick a file, set the size, and the page creates the new image locally using the browser's Canvas technology. Your original photo is never sent to a server.
How to Resize an Image Online
- Add your image. Tap the upload area, drag a file onto it, or paste an image from your clipboard.
- Choose a method. Use Pixels for exact width and height or Percent to scale proportionally.
- Pick a preset (optional). One tap sets common sizes for Instagram, YouTube, WhatsApp, LinkedIn and more.
- Select format and quality. Choose JPG, PNG or WebP, then adjust quality or enter a target size in KB.
- Click Resize. Review the new dimensions and file size, then press Download.
Features of This Image Resizer
Pixel and percent modes
Type exact dimensions or drag the percent slider. With the lock on, changing one value updates the other automatically.
Social media presets
Ready-made sizes save you from searching for platform requirements. Always double-check the platform's current guidance because recommended sizes change.
Rotate and flip
Fix a sideways photo or mirror an image before resizing. The live preview updates immediately.
Target file size
Need a photo under 200 KB for a form? Enter the limit and the tool searches for the best quality that fits.
Reset in one tap
The Reset button clears the image, dimensions, rotation and results so you can start fresh.
Aspect Ratio, Crop and Padding
The aspect ratio is the relationship between width and height. A 1600 × 900 image has a 16:9 ratio. Keeping the ratio locked prevents stretched faces and squashed logos.
When dimensions do not match
If a form demands exactly 600 × 600 but your photo is landscape, you have three options:
- Stretch forces the image into the box and distorts it.
- Fill (crop) covers the whole box and trims the edges.
- Fit (padding) shows the whole image and adds background colour around it.
JPG vs PNG vs WebP
JPG
Best for photographs. It uses lossy compression, so lowering quality reduces file size. JPG has no transparency, so transparent areas are filled with your background colour.
PNG
Lossless and supports transparency, which suits logos, screenshots and graphics. Quality and target-size settings do not apply, so reduce dimensions to shrink a PNG.
WebP
A modern format that often produces smaller files than JPG at similar quality and supports transparency. It works in all current major browsers.
Quick rule
Photos: JPG or WebP. Logos and transparency: PNG or WebP.
Resize an Image to a Specific KB Size
Dimensions and compression both influence file size. Fewer pixels means fewer bytes, and lower quality shrinks JPG and WebP further. For a target size, enter the KB limit and click Resize. If the limit is too strict for the chosen dimensions, the tool tells you and gives the smallest result it could reach. Lower the width and height and try again.
Related tools: convert units with our file size converter, clean up photos with the online document scanner, or build graphics with the meme generator and QR code generator. Browse more on the Floan homepage.
Image Resizing Best Practices
- Keep the original. Always resize a copy.
- Avoid big enlargements. Upscaling cannot create missing detail.
- Match the display size. A 4000 px image in a 400 px slot wastes bandwidth.
- Preserve proportions unless a design needs exact dimensions.
- Check the result before publishing.
For technical background, read MDN on Canvas drawImage and toBlob, plus Google's image SEO best practices and web.dev's Learn Images course.