Image Resize
Change the dimensions of your image, with optional aspect-ratio lock.
Select an image
or drag & drop it here
About the Image Resizer
Change an image's exact width and height in pixels — the requirement most application forms, website builders and document templates actually check. Type the dimensions you need, keep the aspect ratio locked so nothing stretches, or unlock it for a deliberate distortion. Quick 25%, 50% and 75% buttons handle common halving jobs in one click. Resizing runs on your device and downloads as a crisp PNG.
Who needs exact pixels
Exam portals specify photo boxes like 200×230 px; job applications ask for signature scans at fixed dimensions; ad platforms and marketplaces publish recommended creative sizes. Scaling by percentage is equally handy — halving a 4000-pixel-wide phone photo to 2000 makes it far lighter while staying sharp enough for any screen. Whatever the target, the workflow is the same: load the image, type or click your way to the numbers, download.
Aspect ratio: lock vs unlock
The padlock between the two fields is on by default, and it deserves respect. With it engaged, editing either dimension recalculates the other proportionally, so a 4000×3000 photo resized to 1000 wide becomes 750 tall — geometry preserved, faces round. Unlock it only when you intentionally want to squash or stretch: fitting a logo into a non-standard banner slot, for example. Forcing a portrait photo into unrelated dimensions without cropping will visibly distort people, which is why a crop-first approach (see Image Crop) often pairs better with resizing than unlocking does.
Downscaling vs upscaling
Making images smaller is mathematically safe: the browser samples multiple source pixels per output pixel using high-quality smoothing, so text stays readable and edges stay clean down to fairly extreme reductions. Enlarging is the opposite — the tool will happily upscale, but the engine must invent pixels that were never captured, so big enlargements soften noticeably. As a rule of thumb, upscaling past about 150% starts looking mushy; if a form rejects a small scan, rescanning at higher settings beats enlarging the old file.
Output details worth knowing
Results download as PNG, which is lossless — the resized pixels are stored exactly as rendered, with no additional generational quality loss, and transparency is preserved. The filename carries the final dimensions, which makes it easy to confirm you produced the right size before uploading anywhere.
Video slot: image-resize-walkthrough.mp4
A demonstration resizing a 4000-pixel phone photo to form-spec dimensions with the lock on, plus the 50% shortcut and a comparison of the downloaded PNG's dimensions.
Coming soonHow to Use Image Resizer Online
Follow these simple steps to use Image Resizer securely in your web browser.
- 1
Upload Photo
Select or drop an image into the browser resizer window.
01-image-resize-upload-photo.png
Replace with a real capture
- 2
Adjust Dimensions
Enter desired width and height in pixels or adjust percentage scaling.
02-image-resize-adjust-dimensions.png
Replace with a real capture
- 3
Download Resized Image
Click download to save the resized image file to your device.
03-image-resize-download-resized-image.png
Replace with a real capture
Features & Specifications
Resizing Engine
HTML5 Canvas 2D drawImage
Supported Formats
JPG, PNG, WebP
Interpolation
High-Quality Bicubic Smoothing
Privacy Status
100% Local In-Browser Processing
100% Free & Private In-Browser Processing
Rupix operates on a zero-upload architecture. All computations, file parsing, and transformations occur locally inside your web browser. No document bytes, sensitive text, or personal data are ever uploaded or transmitted to remote servers.
Why use Rupix Image Resizer?
Aspect Ratio Lock
Proportionally scale dimensions to prevent distortion or stretching.
Pixel & Percentage Controls
Scale by exact pixel boundaries or standard percentages (25%, 50%, 75%).
Fast Canvas Rendering
Instant image resampling with sharp bicubic interpolation.