Image Compressor
Compress images while preserving quality. Supports JPG, PNG, and WebP. Processes up to 5 images at once.
What this tool actually does
The Image Compressor decodes each picture with your browser's Canvas API, redraws it at its original pixel dimensions, and re-encodes it at the quality you choose. Nothing is resized and nothing is cropped — the savings come purely from smarter lossy encoding, which discards visual detail your eye is least likely to notice. You can process up to five images in one batch, compare each preview against the original, and download the ones you're happy with.
A worked example
A 12-megapixel photo straight off a phone camera is typically around 3.30 MB as a JPEG, because cameras encode at very high quality (roughly 92–98) to preserve editing headroom. Re-encoding it here at quality 75 usually lands near 793.4 KB — a ~77% reduction that is very hard to distinguish from the original on screen. Dropping to quality 60 pushes it to roughly 489.4 KB, where fine textures like hair and foliage begin to soften. Exact numbers depend on the image content: photos with smooth skies compress dramatically, busy textures less so.
Picking a quality value
For photos going into a web page or chat message, 70–80 is the sweet spot. For thumbnails and previews, 50–65 is fine. Above 85 file sizes climb steeply for gains you can't see; below 40 block artifacts become visible in flat areas. If you're compressing screenshots with sharp text, stay at 80+ — text edges show JPEG artifacts sooner than photographs do.
A note on PNG and GIF
PNG is a lossless format, so the quality slider does not apply to it — browsers ignore the quality parameter when encoding PNG. A PNG run through this tool is simply re-encoded and may shrink only slightly (or occasionally grow). If a PNG photo is too big, convert it to JPEG or WebP with the File Converter first. Animated GIFs are decoded to their first frame only — the Canvas API has no access to the remaining frames — so use a dedicated GIF optimizer for animations.
How to use Image Compressor
- 1Upload up to 5 images (JPG, PNG, or WebP work best).
- 2Adjust the quality slider to balance size and quality.
- 3Click 'Compress All' to process them at once.
- 4Compare each preview, then download the results you want.
Frequently Asked Questions
Will it reduce my image's resolution?
No. Pixel dimensions stay exactly the same — only the encoding quality changes. If you also want smaller dimensions, resize before compressing.
Which formats are supported?
JPG, PNG, and WebP keep their format on output. Other browser-readable images are re-encoded as JPEG. Animated GIFs are flattened to their first frame.
Why didn't my PNG get smaller?
PNG is lossless, and browsers ignore the quality setting for it. Convert the image to JPEG or WebP first if you need big savings.
Is there a batch limit?
Yes, 5 images at a time. Each image is held in memory while processing, so the cap keeps the tool responsive on ordinary hardware.
Where are my images uploaded?
Nowhere. Decoding, re-encoding, and preview all happen locally through the Canvas API — the images never leave your device.
Limitations & Privacy
- Quality-based compression applies to lossy formats (JPEG, WebP). PNGs are re-encoded losslessly and may barely shrink.
- Animated GIFs lose their animation — only the first frame is processed.
- Canvas re-encoding does not preserve EXIF metadata (camera model, GPS location). That's often a privacy win, but keep the original if you need the metadata.
- Extremely large images (100+ megapixels) can exceed the browser's canvas size limits, especially on mobile.
- Privacy: images are processed entirely in your browser's memory and are never uploaded.