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Image Tools · Private, local processing

Image Resizer

Resize an image to exact dimensions while keeping its proportions. The selected image is processed on your device.

PNG, JPEG, and WebP · up to 25 MB per image, 100 MB combined, and 30 megapixels per image. Files are not uploaded.

Processing happens locally in your browser. High-resolution images use more memory; output formats and compression quality depend on browser support.

Free online tool

How to use Image Resizer

Select a PNG, JPEG, or WebP image to see its current pixel dimensions. Enter a new width or height and leave the aspect-ratio option enabled to calculate the other dimension without stretching the image. Choose an output format and, where available, adjust the quality before resizing. The result appears in a preview so you can compare its dimensions and appearance before downloading. Processing happens in your browser; the selected image is not uploaded. To avoid excessive memory use, the tool limits input and output images to 30 megapixels and each input to 25 MB. Quality settings trade visual detail for smaller encoded output, but the result size depends on the image and format. PNG quality adjustment uses a lossy WebP intermediate before converting back to PNG, so it can reduce fidelity without guaranteeing a smaller PNG. Keep the original when quality matters. If preview generation is slow, close unused tabs and retry. Transparent pixels can look different against dark and light backgrounds, so inspect the output against the background where it will be used.

How it works

  1. Choose a PNG, JPEG, or WebP image and note its source dimensions.
  2. Set the output width and height; keep the aspect ratio selected unless you intentionally want to stretch the image.
  3. Choose an output format and quality, resize, review the preview, and download the new file.

Examples and common errors

Resize while preserving proportions

Input or situation

1200 × 800 px image; set width to 600 px

Expected result or advice

600 × 400 px when the aspect-ratio option is enabled.

Prepare a square thumbnail

Input or situation

1200 × 800 px image; set width to 600 and height to 600 with ratio disabled

Expected result or advice

A 600 × 600 px image; disabling the ratio can distort the source.

PNG quality note

Input or situation

PNG output with a lower quality setting

Expected result or advice

The visual quality can decrease, but the resulting PNG is not guaranteed to be smaller.

Frequently asked questions

Does resizing change my original image?

No. The tool creates a separate output file and leaves the source image unchanged.

Can I preserve the original proportions?

Yes. Keep the aspect-ratio option enabled; changing one dimension updates the other.

Can I adjust quality for PNG output?

Yes. PNG quality uses a lossy WebP intermediate before converting back to PNG. It may reduce image fidelity and does not guarantee a smaller file.

What formats and sizes are supported?

PNG, JPEG, and WebP are supported. Each input must be 25 MB or smaller, and input and output images are limited to 30 megapixels.

Is my image uploaded?

No. The browser decodes, resizes, and encodes the image locally on your device.