How to Compress Images Without Losing Quality
Reduce image file size with precise quality control. Adjust compression, change format, compare before and after. Free, private, runs in your browser.
The problem
Your image is 4MB and you need it under 500KB for a website, an email attachment, or a CMS upload limit. You know there's a quality tradeoff — but most tools don't let you see it. They either auto-compress with no control, or they're Photoshop and you have to install something.
What you want is a slider that shows you exactly how much quality you're trading for how much file size reduction. In real time, before you commit.
How it works
- Upload your image — drag and drop or click to browse. Supports PNG, JPG, and WebP.
- Adjust the quality slider — move it from 1 to 100 and watch the output file size update live. The before/after comparison shows you exactly what you're saving.
- Pick an output format — keep the original format, or switch to JPG (smaller for photos), PNG (lossless), or WebP (best of both).
- Optional: resize — if you want to reduce dimensions at the same time, toggle the resize controls.
- Download — the compressed image saves with a clear filename showing the format.
Everything runs in your browser. Your photos stay on your device.
How much compression is too much?
It depends on the content:
- Photos (faces, landscapes): JPG quality 70-85 is usually imperceptible. Below 60, you'll start seeing artifacts around edges.
- Screenshots and text: PNG is better — it's lossless. If you must use JPG, stay above 90.
- Web graphics: WebP at quality 75-80 gives smaller files than JPG at equivalent visual quality.
- Thumbnails: You can go lower (50-60) because small images hide artifacts.
The compressor shows file size at every quality level, so you can find the sweet spot for your specific image instead of guessing.
JPEG vs WebP vs PNG — which format to pick
- JPEG: Universal compatibility. Best for photographs. Doesn't support transparency.
- WebP: 25-35% smaller than JPEG at the same visual quality. Supported by all modern browsers. Use this for web images when you don't need IE11 support.
- PNG: Lossless compression. Supports transparency. Larger files. Use for screenshots, logos, and graphics with sharp edges or text.
If you're compressing for a website, WebP is almost always the right choice. For email attachments or documents, JPEG is safer because every device can open it.
Built with vanilla HTML/JS. No frameworks, no backend, loads instantly.