What does an image resizer do?
An image resizer changes an image's pixel dimensions to a target width and height or a preset size. This tool runs in your browser using the Canvas API, and the page states that images are not uploaded.
Choosing a resize mode
Three modes control what happens when your target dimensions don't share the same aspect ratio as the source image:
- Fit keeps the whole image visible inside the target box. Leftover space uses the selected background color or the Transparent option.
- Fill covers the target box and crops the overhang at the edges.
- Exact matches the target width and height, even when that changes the image's proportions.
When files with different source proportions are processed together, Fit or Fill can produce different padding or cropping for each file.
Set dimensions and preserve proportions
Enter the target width and height in the Dimensions (px) fields. They initially display 1080 by 1080, and you can replace either value. Use the link control between the fields to preserve the source proportion while changing a dimension.
The Social media presets buttons enter fixed dimensions for Instagram Post, Instagram Story, Facebook Post, Facebook Cover, X / Twitter Post, LinkedIn Banner, YouTube Thumbnail, and Pinterest Pin. You can then choose the resize mode for the selected files.
Background, output format, and no-upscale setting
For Fit, choose a color under Fit background or select Transparent for leftover space. Under Output format, choose the source type when supported, JPEG, WebP, or PNG.
Enable Don't enlarge smaller images to prevent smaller files from being enlarged beyond their original pixel dimensions. PNG is a lossless output format, but resizing can still change pixels and cannot restore detail from a soft source.
How to resize images
- Drop images labeled JPG, PNG, WEBP, GIF, BMP, or AVIF onto the drop zone, or use browse files.
- Select one or more images, then choose a preset or enter custom dimensions.
- Choose Fit, Fill, or Exact. If you use Fit, configure Fit background and Transparent if needed.
- Choose an Output format and decide whether to enable Don't enlarge smaller images.
- Resizing starts automatically after the images and settings are ready. The file list shows File, Original, New size, and Status.
- Review the Before and After preview, then use Download all as ZIP when it appears.
The selected dimensions and options apply to the batch. Files with different aspect ratios can therefore have different results in Fit or Fill.
Batch behavior and limitations
The local page does not document a numeric maximum for image count, file size, pixel dimensions, or batch size. Do not treat the tool as having unlimited processing; practical results can depend on the browser and the files selected.
Frequently asked questions
What is the difference between fit, fill, and exact resize modes?
Fit shrinks or grows the image to fit entirely inside your target dimensions and fills any leftover space with a background color, so nothing is cropped. Fill scales the image to cover the full target area and crops any overhang, so there is no border but some edges may be trimmed. Exact stretches the image to match your width and height precisely, which can distort the image if the aspect ratio differs.
What does no-upscale protection do?
When enabled, the tool will not enlarge an image beyond its original pixel dimensions, since stretching a small image to a larger size only makes it blurry. If your target size is bigger than the source image, that file is kept at its original size instead.
Will resizing reduce image quality?
Resizing changes the image's pixels. Shrinking removes detail, and enlarging can look soft; the no-upscale setting can prevent enlargement beyond the source dimensions. PNG is a lossless output format, but it cannot restore detail or prevent changes caused by resizing.
Are my images uploaded anywhere?
No. The page states that loading, resizing, and previewing happen in your browser using the Canvas API, so the images are not uploaded to a server.
Is there a limit to how many images I can resize?
No numeric image-count limit is documented on this page. The same selected dimensions and processing options apply to the selected batch, and practical processing can depend on the browser and the files selected.