Image Resize
Image Tools
Resize images to exact dimensions or by scale percentage. Lock aspect ratio, pick output format and quality, then download.
Runs entirely in your browserAbout Image Resize
Resizing images on the fly is one of the most common image chores: scaling photos to a specific upload limit, generating thumbnails, fitting an avatar to a service's required dimensions, or just shrinking a 6000px screenshot down to something embeddable. Doing it in an image editor is overkill; uploading to an online tool feels invasive when the photo is private.
This resizer runs entirely in your browser. Set the exact width and height you want — or set a scale percentage and let the tool calculate — with aspect-ratio lock on by default to prevent stretching. Pick the output format (PNG for lossless, JPEG/WebP for smaller files) and quality. The Canvas API does the resampling with bilinear interpolation, which is the standard fast resize algorithm used by most browsers and image libraries. Originals never leave your machine.
How to use
- 1
Drop an image
Drag and drop, or click to pick.
- 2
Pick a mode
By dimensions for exact width/height; By scale for percentage-based resize. Switch via the tabs.
- 3
Toggle aspect lock
When the link icon shows (default), width and height change together to preserve aspect ratio. Click to break the link and resize freely.
- 4
Pick output format and quality
PNG keeps full quality. JPEG or WebP let you tune quality (smaller files for lossy formats).
- 5
Apply and download
Click Apply resize to render the new image, then Download to save.
Examples
Scale a 6000px screenshot to 1200px wide
Lock aspect on, set width to 1200 — height fills in automatically.
Output
6000×4000 → 1200×800 (75% smaller bytes for typical content)Crop-free thumbnail at 50% scale
Set scale to 50% — both dimensions halve.
Output
2400×1600 → 1200×800Frequently asked questions
Why is the resized image quality good even at small sizes?+
We use the browser's Canvas resampling with high-quality interpolation enabled. For most use cases — downscaling photos and screenshots — this produces results indistinguishable from heavyweight image editors.
Can I upscale an image?+
You can, but the result will look soft. Upscaling can't invent detail that wasn't in the original; the browser's bilinear interpolation just stretches existing pixels. For genuine upscaling, you need an AI-based tool.
Why does the aspect lock break dimensions when I type?+
With lock on, editing width auto-updates height and vice versa. If both look 'off', you may be editing a value that's been rounded from the previous edit — clear and start over, or break the lock for free editing.
What's the maximum image size?+
Browser canvases are usually capped around 16384px in any dimension, but practical limits depend on memory. For multi-gigabyte source files, downscale first then crop.
Is the image uploaded?+
No. All resizing runs locally in your browser.
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