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Image Compressor

Reduce the file size of JPG, PNG, and WebP photos right in the browser. The image is decoded, resized, and re-encoded on your device — nothing is uploaded to a server.

All processing happens locally, in your browser. The image never leaves your device.

How to use

Add a file (drag, pick) or paste an image from the clipboard.
Adjust quality and, optionally, the maximum width.
Download or copy the lighter version.

Supported formats

Format	Input	Output	Strategy
JPEG	yes	JPEG	Lossy re-encoding (adjustable quality)
WebP	yes	WebP	Lossy re-encoding (adjustable quality)
PNG	yes	PNG	Lossless optimization (keeps the smaller result)

The output format always matches the input — the tool does not convert between formats.

Quality

Range 10 to 100; the default is 80.
For JPEG and WebP at the default quality, the tool runs an adaptive pass: it automatically finds the highest quality that still keeps the file smaller than the original.
PNG has no quality setting: optimization is always lossless.

Resizing

By default, the maximum width is automatic: images wider than 1920px are scaled down to 1920px; smaller images keep their size.
You can set a specific maximum width. Height is scaled proportionally.

When the original file is kept

If there was no intentional resize, re-encoding did not make the file smaller, and quality is at (or above) the default, the tool returns the original file without re-compressing.

This avoids making already-optimized images worse — instead of a larger file, you get the original untouched.

Technology used

Browser Canvas to decode and resize the image.
WebAssembly (jSquash) to re-encode JPEG and WebP and optimize PNG — the same codecs used by modern image tools, running locally.

Technical details

Two-step pipeline: the image is decoded once (ingest) and re-encoded whenever an option changes (transform).
The JPEG and WebP encoders and the PNG optimization run via WebAssembly in the browser.