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Image Utility

Image Resizer

Resize the width and height of JPG, PNG, and WEBP images. Keep the aspect ratio, use quick reduction presets, and adjust output quality and transparency.

Private Browser Processing Process images directly in your current browser without sending or storing them on a server.
Aspect Ratio and Presets Keep the original ratio or quickly reduce the image to 25%, 50%, or 75% of its original size.
Compare Result Details Review original and result dimensions, scale percentage, and file size before downloading.
STEP 1

Upload an Image

Choose one JPG, PNG, or WEBP image to resize.

Privacy Your image is never sent over the network. The result is newly generated and does not include the original EXIF or location metadata.
Practical guide

Resize images to a required width or height

Pixel dimensions describe the image grid; file size describes the encoded file. Reducing width does not guarantee a smaller file. Set the required dimensions, preserve the aspect ratio when appropriate, then inspect the saved size and appearance.

Prepared & reviewed by
win-j
Last reviewed
2026-09-30

Who this helps

  • People preparing blog photos, product images or application attachments.
  • People resizing a transparent logo without stretching it.

When to use this tool

  • Fit a 4032×3024 photo into a 1200-pixel-wide article.
  • Meet a width requirement while keeping the full image visible.

From input to a checked result

  1. 1

    Choose a JPEG, PNG or WebP image and check its original dimensions. The input limit is 40 MiB and 60 million pixels.

  2. 2

    Enable the aspect-ratio lock, then enter the required width or height.

  3. 3

    Keep Prevent upscaling enabled unless enlargement is intentional. Output dimensions are limited to 12,000 per side and 60 million pixels.

  4. 4

    Choose JPEG for a flat background, or PNG/WebP when transparency is needed. Compare JPEG/WebP quality with the preview.

  5. 5

    Download and check the actual dimensions, file size and small text at its intended display size.

Example 1

A blog photo

Input
4032×3024; width 1200; aspect ratio locked
Result
1200×900 pixels.

This is the dimension calculation. The final byte count depends on format, quality and image content.

Example 2

A square requirement is not a crop

Input
1200×800; width 300; aspect ratio locked
Result
300×200 pixels, with the complete image retained.

This tool resizes rather than crops. Unlocking the ratio and entering 300×300 stretches the image. Crop separately first if a square image is required.

How it works

The browser decodes the image and draws it on a canvas at the requested dimensions. With the ratio locked, the other side is recalculated and rounded to a whole pixel. Prevent upscaling caps dimensions against the original. JPEG and WebP quality is passed to the browser encoder.

Limitations

  • Enlargement adds pixels but does not recover missing detail.
  • Changing dimensions is not the same as cropping to a composition or meeting an exact file-size limit.
  • Metadata and color profiles may change during canvas export; check the output if those matter.
  • Large images may still exceed the memory available on a phone.
Your data

Image processing takes place in your browser. This tool does not upload or store the selected or resulting file on the win-j server.

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Frequently asked questions

Why does changing the width also change the height?

The ratio lock keeps the original proportions. Turn it off only when changing the shape is intentional.

Can I make a 300×300 square photo here?

You can set both dimensions, but this does not crop the image. A non-square source will be distorted if the ratio is unlocked. Crop to a square before resizing.

Does quality 80 reduce file size by 20%?

No. It is an encoder setting. Compare the actual output bytes and visual detail.

Can resizing improve a blurry original?

A larger grid cannot recreate missing detail. Use a higher-resolution original when possible.