Pixora guide · Updated September 21, 2026
How to Resize an Image Online
Learn how to change image dimensions with exact controls, aspect-ratio protection and batch processing.
Open Image Resizer →What this guide covers
This guide focuses on the practical decisions behind image editing: pixel dimensions, file formats, compression settings, browser support and the final destination of the image. The goal is to help you choose a workflow based on the actual requirement rather than simply producing the smallest possible file.
What resizing actually changes
Resizing changes the number of pixels used to represent an image. It is different from cropping: resizing keeps the composition while changing its dimensions, whereas cropping removes part of the image.
1. Choose the source
Open Pixora's Image Resizer and select one or more browser-readable images. Keep the original files so you can create another version if the destination changes.
2. Set the required dimensions
Enter the width and height required by the destination. Keep the aspect-ratio lock enabled when you want proportional scaling. Unlock it only when the destination explicitly requires independent width and height values.
3. Preview the result
Process the image and inspect the output. Look for stretched subjects, softened small text, unexpected orientation issues and other changes that may not be obvious from the numbers alone.
4. Choose the output format
For photographs, JPG can be practical. PNG can be useful when transparency or lossless output matters, while WebP can be useful for supported web destinations. The best choice depends on where the image will be used.
Batch resizing
When several images share the same destination dimensions, batch processing can save time. Make sure the same settings are appropriate for every source before processing the whole group.
Related resizing workflows
See Instagram resizing, YouTube resizing and Facebook resizing for focused presets.