Are my images uploaded to any server during compression?

Never. Decoding, resizing, compression, and ZIP creation all run locally inside your browser.

What quality setting is best for web images?

A quality setting between 75% and 85% typically reduces file size by over 70% while remaining visually crisp on high-DPI displays.

Why does an already-optimized image show 0% saved?

Re-encoding can increase file size. Without a width limit, the original is kept if the output is not smaller; with a width limit, the output may still be larger.

100% Browser-Based · Zero Server Uploads

Local Image Compressor (WebP / PNG / JPEG)

Output format

Quality / colour quantization (80%)

Limit maximum width

Results

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Total space saved

—

0 images · 0 B → —

Original size0 B

Compressed size—

All images are compressed locally via HTML5 Canvas and never uploaded to any server. If an output exceeds the original size, the original file is kept automatically.

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Method and common questions

Tax, lending, holiday and protection rules vary by place and date. Check current local rules and provider terms. Results are estimates.

Why Compress Images Locally in the Browser?

Page speed and Largest Contentful Paint (LCP) directly impact search rankings and conversion rates. Converting raw multi-megabyte photos into WebP or quantized PNGs typically cuts file size by 60%–85% with virtually no visible loss.

This tool uses browser Canvas to process images without uploading them first. Speed and image capacity depend on your device and browser.

Use WebP for web articles and e-commerce thumbnails to combine transparency with small file sizes.
Without a width limit, the original is kept if the output is not smaller. A width-limited output may still be larger.

Choosing Between WebP, PNG, and JPEG

Photographs compress best as WebP or JPEG at 75%–85% quality, while UI screenshots, logos, and diagrams stay sharpest as quantized PNG or WebP.

Method

Images are decoded locally onto an HTML5 Canvas, proportionally resized if a maximum width cap is enabled, encoded to WebP/JPEG or posterized/quantized PNG, and packaged into a standard ZIP binary stream in memory.

FAQ

Are my images uploaded to any server during compression?: Never. Decoding, resizing, compression, and ZIP creation all run locally inside your browser.
What quality setting is best for web images?: A quality setting between 75% and 85% typically reduces file size by over 70% while remaining visually crisp on high-DPI displays.
Why does an already-optimized image show 0% saved?: Re-encoding can increase file size. Without a width limit, the original is kept if the output is not smaller; with a width limit, the output may still be larger.