Free Image Resizer & Dimension Changer

Resize images to exact width and height in your browser. Canvas-based scaling, optional aspect lock, and local processing—no upload to WebTooly.

Common size presets

Tap a size to fill width and height (unlock aspect ratio if you need a different ratio).

Social and cover images

Facebook Cover Photo:
Instagram Post (Square):
Twitter Header:
LinkedIn Banner:

Thumbnails and products

Blog Post Thumbnail:
Product Image:
Gallery Thumbnail:
Hero Banner:

Mobile-oriented

Mobile Banner:
App Icon:
Mobile Card:
Profile Picture:

Email and print

Email Header:
Newsletter Image:
Business Card:
Flyer (A4):

About Image Resizer

HTML5 Canvas 2D: the image is drawn to a canvas at your target width and height, then exported with `toBlob`. Uses the browser’s default canvas scaler—not `pica` or another dedicated resampler.

How it works (technical)

Flow: `Image` from object URL → `canvas.width` / `canvas.height` → `getContext('2d')?.drawImage(img, 0, 0, width, height)` → `toBlob` with `file.type || 'image/jpeg'` at quality `0.9`.

Aspect lock recomputes the other dimension from the file’s native width/height.

Heavy upscaling still softens detail; downscaling is the typical sweet spot.

Processing stays in the browser; no upload of bitmap bytes.

When to use it

  • Exact pixel output

    Match a layout grid or CSS `width`/`height` without opening desktop software.

  • Thumbnails and previews

    Shrink large camera exports before compression or upload.

  • Platform limits

    Fit maximum dimension rules for forms or marketplaces.

How to Use Image Resizer

  1. 1Upload your image by dropping it or clicking to browse.
  2. 2Enter the desired width and height in pixels.
  3. 3Toggle aspect ratio lock to maintain proportions.
  4. 4Click "Resize Image" and download the result.

Key Features

  • `drawImage` to explicit canvas size
  • Aspect lock from native dimensions
  • Preview after load
  • Download resized blob

Benefits

  • Direct pixel dimensions
  • Client-side only
  • Same MIME family as the source file

Frequently Asked Questions

Will resizing affect image quality?

Our resizer uses high-quality algorithms to maintain image clarity. Enlarging images may reduce quality, while reducing size typically maintains good quality.

What happens if I don't maintain aspect ratio?

Disabling aspect ratio lock allows you to set any width and height, which may stretch or compress the image. This is useful for fitting specific dimensions.

What image formats are supported?

We support JPG, JPEG, PNG, and WebP formats. The resized image will maintain the same format as your original file.

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