LazyTools

🔒 Every tool runs in your browser — the files and values you enter are never uploaded to any server. How it works

🗜️ Image Compressor

Shrink image file size with a quality slider and instant before/after comparison — your photo never leaves the browser.

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How the image compressor works

The image is decoded and re-encoded by the browser's own codec at your chosen quality level. Lossy formats (JPEG, WebP) discard detail the eye rarely misses — most photos survive quality 70–85 with no visible change while dropping to a fraction of the size. The size readout updates live so you can find the point where quality loss becomes visible, and re-encoding also strips metadata as a side effect.

The counterintuitive tip: for photographs, converting PNG to JPEG or WebP saves far more than any PNG optimization — PNG is lossless by design and stores photographic noise expensively. Keep PNG for screenshots, diagrams and anything with text or sharp edges, where JPEG artifacts show first.

Frequently asked questions

What quality setting should I use?

For photos, 75–85 is the sweet spot — usually 5–10× smaller than the original with no visible difference at normal viewing size. Go lower for thumbnails, higher (90+) only for print or editing masters.

Why is my PNG barely shrinking?

PNG is lossless — the quality slider doesn't apply, and photographic content compresses poorly in it. Convert photos to JPEG or WebP for major savings; keep PNG for screenshots and graphics with text or transparency.

Does compression remove metadata too?

Yes — re-encoding through the canvas produces a file with pixels only, so EXIF, GPS and other metadata are dropped as a side effect. For metadata specifically, the image metadata remover shows what was present first.

Is WebP better than JPEG?

For the same visual quality, WebP files are typically 25–35% smaller, and WebP supports transparency. Every modern browser displays it; the residual reason to pick JPEG is compatibility with old software and some upload forms.

Is the image uploaded for processing?

No — decoding and re-encoding use the browser's built-in codecs on your device. Nothing is transmitted; the tool works offline.

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