Image Resizer
Resize images by width, height, or percentage right in your browser.
Resize by dimensionsResize by percentageLock aspect ratioBrowser-based processing
Image resizer tool
Upload an image, set a new size by dimensions or percentage, then export it. Processing stays in your browser.
Upload or drag an image
JPG, PNG, or WebP up to 20.00 MB
Images are processed in your browser. They are not uploaded by this tool.
Preview and export
Compare the original and resized image, check the new dimensions, then download the result.
Original
Upload an image to preview it here.
Resized
Resized preview appears here.
Original dimensions
Not uploaded
New dimensions
Not set
Original size
Not uploaded
Resized size
Not resized
Output format
JPG
Quality setting
85%
Resize by dimensions
Set an exact width and height in pixels, with optional aspect-ratio lock.
Resize by percentage
Scale an image up or down by a percentage of its original size.
Browser processing
Images are resized in this page with canvas and are not uploaded.
Dynamic Resize Insights
Upload a JPG, PNG, or WebP image to begin resizing.
Choose custom width and height, or switch to percentage mode.
Aspect ratio is locked, so editing one dimension updates the other to avoid stretching.
Reducing dimensions usually lowers the file size, but enlarging can increase it.
JPG and WebP use a quality setting, so lower quality means smaller files with less detail.
How Image Resizing Works
Resizing changes the pixel width and height of an image.
The image is drawn into a canvas at the target dimensions.
Locking aspect ratio keeps the original proportions.
Percentage mode scales both dimensions by the same factor.
Output format and quality are applied when exporting.
Enlarging cannot add detail that was not in the original.
Width, Height, Percentage, and File Size
Width and height set the exact pixel size of the output.
Aspect ratio lock prevents stretching when editing one dimension.
Percentage is handy when you want half or double the size.
Smaller dimensions usually mean a smaller file.
Enlarging or switching format can increase the file size.
Resizing is about dimensions, while compression is about encoding.
JPG, PNG, and WebP Notes
JPG is efficient for photos but removes transparency.
PNG keeps transparency and uses lossless export, so quality does not apply.
WebP often creates smaller files, but export depends on your browser.
Choosing JPG flattens transparency onto a white background.
Keep the original format when you only need to change the size.
Format support varies, so a fallback to JPG or PNG may be needed.
Common Image Resizing Examples
Resize a photo to 1280px wide for a website.
Scale an image to 50% for a faster email attachment.
Shrink a screenshot to fit a document.
Resize a profile picture to a square size.
Make a product image fit a marketplace limit.
Reduce a large camera photo before uploading.
Resize a banner to exact ad dimensions.
Double a small graphic for a quick mockup.
Privacy and Local Processing Notes
Images are processed in your browser using canvas.
They are not uploaded by this tool and no account is required.
Resizing works offline once the page has loaded.
Use care with personal photos, IDs, or confidential images on shared devices.
Only resize images you own or have permission to use.
Canvas export may remove metadata such as EXIF camera details.
Very large images may be slow or fail on memory-limited browsers.
Review the preview before replacing an original file.
Method Explanation
1. Upload an image and read its original dimensions.
2. Choose custom dimensions or a percentage.
3. Keep the aspect ratio locked to avoid stretching.
4. Pick an output format and, for JPG or WebP, a quality.
5. Draw the image into a canvas at the target size.
6. Export the canvas and preview the result.
7. Download the resized image.
Frequently Asked Questions
Keep the Lock aspect ratio option enabled. When it is on, editing the width updates the height automatically (and the reverse), so the image keeps its original proportions and does not look stretched or squashed.
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Related reading
Learn the formula, assumptions, examples, or context behind this tool.
How to Resize and Compress Images for the WebCovers dimensions, file size, aspect ratio, compression, and choosing image settings for web use.Aspect ratios for images and videoUnderstand how aspect ratios keep images and video from being cropped.File sizes: KB, MB, and GB explainedSee how kilobytes, megabytes, and gigabytes measure image and file size.