Resize Images Online for Free
Change image dimensions instantly. Set custom width and height, scale by percentage, or pick a social-media preset. Your images stay private — all processing happens in your browser.
Multiple Ways to Resize
ImageSizr.com gives you full control over how your images are resized. Enter exact pixel dimensions with aspect-ratio lock to maintain proportions, or scale by percentage using quick presets at 25%, 50%, and 75%.
Need a specific unit? Enter dimensions in pixels, centimetres, inches, or millimetres — non-pixel units are converted automatically using 96 DPI.
For instant results, choose from social-media presets covering Instagram, Facebook, Twitter/X, and YouTube, or pick a device preset for screens from HD to 4K and specific devices like iPhone, iPad, and MacBook.
Flexible Output Formats
Export your resized images in the format that works best for your needs. Keep the original format, or convert to JPEG for smaller photo files, PNG for lossless quality with transparency, or WebP for the best compression-to-quality ratio on the web.
Need an icon? Generate multi-size ICO files containing 16, 32, 48, 64, 128, and 256 px variants — perfect for favicons and desktop icons.
Control quality settings before downloading and set a background colour for transparent images when exporting to JPEG.
Easy Upload, Multiple Sources
Get your images into the editor however is most convenient. Drag and drop files into the upload area, click browse to pick a file, or paste directly from your clipboard with Ctrl/Cmd+V.
You can also import from a URL, Google Drive, Dropbox, or OneDrive. ImageSizr supports PNG, JPG, WebP, GIF, BMP, TIFF, AVIF, SVG, ICO, and HEIC files up to 10 MB each, with up to 5 images at once.
Related Tools
ImageSizr.com is more than a resizer. After resizing, you can further refine your images with these tools:
- Batch resize multiple images — apply the same settings to up to 5 files.
- Crop your images — select exactly the region you want with preset aspect ratios or freeform cropping.
- Compress images — reduce file size without changing dimensions using a quality slider with real-time preview.
Explore our guides and tutorials for tips on getting the best results, or learn more about ImageSizr.
Learn More
Frequently Asked Questions
Is ImageSizr free to use?
Yes. ImageSizr is completely free with no account or sign-up required.
Are my images uploaded to a server?
No. All processing happens directly in your browser. Your images never leave your device, so your data stays private.
How to resize an image?
1. Upload your image using drag-and-drop, browse, clipboard paste, URL, or cloud storage. 2. In the editor, enter new dimensions in the Width and Height fields, use the Scale Percentage slider, or pick a preset. 3. Click Download to save the resized image.
Can I resize to exact social-media dimensions?
Yes. Switch to the Social Media resize mode and choose a platform (Instagram, Facebook, Twitter/X, or YouTube), then select the specific preset such as Profile Picture, Cover Photo, Story, or Thumbnail.
Can I resize for a specific screen or device?
Yes. Use the Screen Size mode to pick from display resolutions (HD, Full HD, QHD, 4K) or specific devices including iPhones, Android phones, iPads, and laptops.
What units can I use for dimensions?
You can enter dimensions in pixels (px), centimetres (cm), inches (inch), or millimetres (mm). Non-pixel units are converted automatically using 96 DPI.
Can I resize multiple images at once?
Yes. Use the Bulk Resize tool to upload up to 5 images and apply the same resize settings to all of them.
How do I keep the original proportions?
Enable the Lock Aspect Ratio option. When locked, changing one dimension automatically adjusts the other to maintain the original proportions.
What image formats are supported?
You can upload PNG, JPG/JPEG, WebP, GIF, BMP, TIFF, AVIF, SVG, ICO, and HEIC files. Output formats include the original format, JPEG, PNG, WebP, and ICO.
What is the maximum file size?
Each file can be up to 10 MB.