How to compress images
- Drop one or more JPG, PNG, WebP or HEIC images onto the upload area. You can compress a whole batch at once.
- Set the Quality slider (30–100, default 80). Lower values give smaller files.
- Optionally enter a Max width in pixels to downscale large photos at the same time. Leave it at
0to keep the original dimensions. - Choose the Output format: keep the same format, or convert to JPG or WebP for extra savings.
- Click Compress images and download the results.
Compression runs entirely in your browser: your photos are never uploaded, which is ideal for personal pictures, ID scans and unreleased product shots.
How image compression works
Most of the size of a photo is detail the human eye barely notices. Compression removes that redundancy:
- JPG and WebP are re-encoded with lossy compression at the quality you choose. Fine textures and colour transitions are simplified in ways that are hard to see at normal viewing sizes.
- PNG is lossless, so re-saving it at "quality 80" would change nothing. Instead, the tool colour-quantises PNGs: it reduces the image to an optimised palette of colours, the same technique used by tools like TinyPNG. This is lossy, but for screenshots, icons and graphics the difference is usually invisible while the file shrinks dramatically. Transparency is preserved.
- Resizing often saves the most. A 4000-pixel-wide phone photo shown at 1200 pixels on a website carries more than ten times as many pixels as needed.
Which quality setting should I use?
| Quality | Result | Good for |
|---|---|---|
| 85–100 | Near-original, modest savings | Photography portfolios, print |
| 70–85 | Large savings, differences hard to spot | Websites, blogs, online shops |
| 30–70 | Smallest files, visible artefacts at low values | Thumbnails, email attachments, previews |
Tips for smaller files
- Combine compression and resizing. Setting a max width of 1600–2000 px for web photos typically saves far more than lowering quality alone.
- Try WebP. Converting to WebP usually gives the smallest files at a given visual quality, and all modern browsers display it.
- Photos with transparency: converting a PNG to JPG fills transparent areas with white, so keep PNG or choose WebP if you need a transparent background.
- Don't compress repeatedly. Each lossy save discards a little more detail. Start from the original whenever possible.
- If the result is larger than the original (which can happen with already-optimised files), simply keep the original.
Frequently asked questions
How much smaller will my images get?
It depends on the image. Large camera photos often shrink by 50–80% at quality 80, especially when combined with a max width. Small or already-optimised images save less.
Does compressing PNG lose quality?
Yes, slightly. PNGs are reduced to an optimised colour palette, which is lossy but usually invisible for graphics and screenshots. Photos with smooth gradients may show slight banding; for those, WebP or JPG is often the better choice.
Is there a limit on the number of images?
There is no fixed limit. Because processing happens on your device, very large batches depend on your computer's speed and memory.