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Image Compressor

Compress JPG, PNG, or WebP images locally in your browser. Drag and drop a batch, set a max size or quality target, and download — your images never leave your device.

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

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

  2. Pick a max file size and (optionally) a target format.

  3. Wait a moment — each image compresses locally.

  4. Click to download individually, or download all as a batch.

When to use it

  • Shrinking screenshots before pasting into docs or tickets.

  • Optimising product photos for a webshop without leaking them.

  • Compressing assets to fit under email attachment limits.

  • Batch-converting PNG screenshots to WebP for blog posts.

What it fixes

  • Free online compressors that paywall the download or upscale ads.

  • Privacy concerns about uploading internal screenshots.

  • Native macOS / Windows tools that lack batch settings.

About Image Compressor

Most online image compressors upload to a server. That's a problem for screenshots of internal dashboards, product mockups under NDA, or anything else you'd rather not hand to a third party.

This compressor uses the browser's Canvas + WebCodecs APIs to re-encode images locally. Drop in one or many, choose a target file size or quality, and watch each one compress with a before/after comparison. Output format can be left alone or converted to WebP for max savings.

References: MDN — HTMLCanvasElement.toBlob · Google web.dev — Image formats

Frequently asked

  • Does this upload my images?

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

  • Why is the output bigger than the input?

    Some PNGs and already-optimised JPGs can't be compressed further with browser-native re-encoding. The tool will keep the smaller of the two.

  • What format should I export?

    WebP gives the best size/quality tradeoff for photos and supports transparency. JPG is universal. PNG is best for screenshots, logos, and anything with transparency where WebP isn't supported.

  • What's the max file size?

    Limited by your browser's memory. Most laptops handle 50 MB images comfortably; very large RAW or panorama files may stutter.

Discussion

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