Image Resizer
Resize JPG, PNG and WebP images online by width, height or percentage while keeping the original file unchanged.
Resize Images
Resize JPG, PNG and WebP images online by changing their dimensions without editing the original file.
Choose the width and height you need, keep the original aspect ratio when appropriate, and create a separate resized image for downloads or uploads.
What is an Image Resizer?
An Image Resizer is an online tool that lets you change the width and height of an image to suit your needs. Resizing can help you prepare images for websites, online forms, product listings, social media posts, presentations, and other digital uses that require specific image dimensions.
With the free online Image Resizer from iToolsEra, you can resize JPG, PNG, and WebP images by entering custom dimensions in pixels or choosing a percentage-based size. The aspect-ratio lock helps you maintain the original proportions while changing image dimensions.
You can upload up to 10 images at a time, with a maximum file size of 20 MB per image. Each image can have its own resizing settings, making it convenient to prepare several images for different purposes in one session.
The tool also provides before-and-after previews, including image dimensions and file-size information, so you can review the results before downloading your resized images.
If you need to change an image's dimensions for an upload requirement or a particular display area, iToolsEra provides a simple way to resize your images online without installing desktop software.
How Does Image Resizing Work?
Image resizing changes the number of pixels in an image's width and height. For example, resizing an image from 2400 × 1600 pixels to 1200 × 800 pixels reduces its dimensions while maintaining the same proportions.
The iToolsEra Image Resizer lets you control image dimensions using pixel values or percentage-based resizing.
Follow these steps:
- Upload your images. Select JPG, PNG, or WebP images. You can upload up to 10 images at once, with a maximum size of 20 MB per image.
- Choose your resizing method. Enter the desired width and height in pixels, or resize by percentage.
- Maintain the aspect ratio. Keep the aspect-ratio lock enabled when you want to preserve the original proportions and avoid unintended stretching.
- Adjust individual images. Set the dimensions or resizing percentage for each image according to its intended use.
- Preview the results. Compare the original and resized images, including their dimensions and file-size information.
- Download your resized images. Once you are satisfied with the results, download the processed images individually.
Pixel-based resizing is useful when a website, application, or form requires specific dimensions. Percentage-based resizing is convenient when you want to scale an image relative to its original size.
Resizing changes image dimensions, while compression focuses on reducing the amount of data stored in an image file. Resizing can also change file size, but it does not guarantee a particular output size in KB.
For the best result, choose dimensions that fit your intended use and review the preview before downloading.
Tips for Resizing Images Correctly
1. Choose dimensions for your intended use.
Before resizing, check the width and height required by the website, application, form, or platform where you plan to use the image.
2. Keep the aspect ratio locked when possible.
Maintaining the original proportions helps prevent images from appearing stretched or compressed. If you need specific dimensions that use different proportions, consider whether cropping or another adjustment is more appropriate.
3. Use pixel dimensions for exact requirements.
If a platform requests an image of a particular width and height, enter those pixel values rather than estimating the size visually.
4. Use percentage resizing for proportional scaling.
Percentage-based resizing is useful when you want to make an image larger or smaller relative to its original dimensions.
5. Resize each image for its purpose.
Product photos, website banners, profile pictures, and small thumbnails may require different dimensions. Use individual image settings when preparing multiple images for different destinations.
6. Check the preview before downloading.
Review the resized dimensions and appearance to make sure the result suits your needs. Pay attention to text, fine details, and edges.
7. Understand how resizing affects quality.
Reducing dimensions removes pixels from the output, while enlarging an image creates additional pixels through resampling. Enlarged images may look softer or less detailed than the original.
8. Use batch resizing when convenient.
You can upload up to 10 images in one session. This can save time when preparing several images for a website, online store, or project.
9. Do not confuse resizing with compression.
Resizing changes pixel dimensions. Compression targets file size. If your image already has the correct dimensions but exceeds a file-size limit, an image compressor may be more appropriate.
10. Check the final file requirements.
If a website specifies both dimensions and a maximum file size, verify both requirements after resizing. The resulting file size depends on the image and its format, so resizing alone may not meet a strict KB limit.
Helpful Guides
Learn how to use this tool for common real-world tasks.