🗜️ Free · private · in-browser
Compress images online — free, private, in your browser
Shrink JPG, PNG, and WebP file sizes without visible quality loss.
Drop images here or click to choose
JPG · PNG · WebP — processed on your device
Why compress images?
Image files are usually the heaviest thing on a web page, in an email, or in a form upload. A photo straight off a modern phone is 3–8 MB — but the version people actually need is almost always under 500 KB. Compressing images makes pages load faster (a direct ranking factor for search engines), keeps you under attachment and upload limits, and saves storage and bandwidth on both ends.
This compressor re-encodes your image at a quality level you control. Lossy formats like JPEG and WebP work by discarding detail the human eye barely registers — at quality 75–85 the difference is usually invisible, while the file shrinks by more than half. The live before/after size readout lets you find the sweet spot for each image instead of guessing.
How to compress an image
- Drop your images onto the panel above (or click to browse). You can add several at once.
- Pick a quality level. 80 is a safe default; drop toward 60 for maximum savings, raise toward 90 for print-adjacent work.
- Choose an output format — or leave “Auto,” which keeps JPEGs as JPEG and converts oversized PNG photos to WebP for much larger savings.
- Download. Each result shows the old size, the new size, and the percentage saved.
Choosing the right format
JPG remains the safest choice for photos going somewhere unknown — every app, browser, and CMS on earth opens it. WebP compresses 25–35% smaller than JPEG at the same visual quality and is supported by every modern browser, making it the best pick for the web. PNG is lossless and the right call for screenshots with sharp text, logos, and images that need transparency — but never for photographs, where it produces files five to ten times larger than necessary.
Privacy: your files stay on your device
Unlike most “online compressors,” FileNimbus never uploads your images. The entire pipeline — decode, re-encode, download — runs in your browser’s memory. That means no waiting on an upload bar, no server storing your photos, and nothing to delete afterwards. It also means the tool works offline once the page is open. Create a free account if you’d like FileNimbus to remember your compression history across visits.
Frequently asked questions
Are my photos uploaded to a server?
No. Compression runs entirely in your browser using the HTML5 canvas — your images never leave your device, which also makes this one of the fastest compressors available.
How much smaller will my image get?
Photographs typically shrink 60–90% at quality 70–80 with no visible difference. Screenshots and graphics vary more; try the slider and watch the live size readout.
What formats are supported?
JPG, PNG, and WebP input. Output defaults to the same family, but PNGs are re-encoded to lossy WebP or JPEG when that saves dramatically more space — you can pick the output format.
Is there a file-size or usage limit?
No hard limits. Very large images (over ~50 megapixels) may be slow on older phones because your own device does the work.
Does compressing reduce image dimensions?
No — this tool keeps the original width and height and reduces file size by re-encoding. If you also want smaller dimensions, run the image through our Image Resizer first for even bigger savings.