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Image Resizer

Resize JPG, PNG, or WebP images locally in your browser. Set a target width and height, keep aspect ratio, fit or fill, and download — nothing leaves your device.

  • Runs in browser
  • No signup
  • No tracking
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How to use Image Resizer

  1. Drop one or more images onto the upload area.

  2. Set target width and height — toggle 'Keep aspect' to preserve ratio.

  3. Pick Fit (no crop), Fill (crop to fit), or Stretch.

  4. Choose output format and quality, then download each result.

When to use it

  • Prepping blog post hero images at exact pixel dimensions.

  • Resizing product photos to a webshop's required size.

  • Shrinking screenshots to fit GitHub README image limits.

  • Generating thumbnails from a batch of source images.

What it fixes

  • Online resizers that watermark output or require signup.

  • Privacy concerns about uploading internal screenshots.

  • Native tools that don't batch-process with consistent settings.

About Image Resizer

Most online resizers upload your images to a server and add a watermark or paywall the bulk download. This tool runs entirely in your browser using the Canvas API: drop one or many images, set target pixels, choose fit (no crop), fill (center crop), or stretch, and download.

Batch mode resizes each image with the same settings — useful for prepping a folder of screenshots for a blog, or shrinking product photos before upload. Format conversion is built in: keep the original or re-encode to JPG, PNG, or WebP.

References: MDN — CanvasRenderingContext2D.drawImage · MDN — createImageBitmap

Frequently asked

  • Does this upload my images?

    No. Resizing runs entirely in your browser via the Canvas API. Images never leave your device.

  • What's the difference between Fit, Fill, and Stretch?

    Fit scales the image to fit inside the target box without cropping (final dimensions may be smaller). Fill scales and centers-crops to exactly the target box. Stretch ignores aspect ratio and forces the exact dimensions.

  • Why does the output look soft?

    Browser canvas resampling is good but not perfect. For best quality, downscale by a factor of two or use high-quality format (PNG/WebP) at quality 0.9+.

  • Can I batch-resize many images?

    Yes. Drop or select multiple files at once — each is resized in sequence and listed with a download button.

Discussion

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