Large images slow down websites, fill up inboxes and get rejected by upload forms. The good news is that most photos can be made much smaller with no difference you can see. This guide explains why images are big, which quality setting to use, and how to compress JPG, PNG and WEBP images for free.
Short answer: open the Image Compressor, select your images, set the quality slider to around 70 to 80 percent, compare the size before and after, and download. It runs in your browser, so your images are not uploaded.
How to compress images online
- Open the Image Compressor.
- Select one or more images.
- Adjust the quality slider. It starts at 75 percent.
- Click Compress images, check the new size and download the result.
Which quality should I choose?
Around 70 to 80 percent gives a big size reduction with almost no visible difference, so start at 75 and look at the result. Then adjust:
| Use | Starting point |
|---|---|
| Website or blog photos | 70 to 80 percent |
| Email attachments | 60 to 75 percent |
| Social media | 75 to 85 percent, platforms recompress again |
| Printing | 85 percent or higher, and keep the original |
These are starting points, not rules. View the compressed image at the size people will see it. If you notice blocky patches or fuzzy edges, raise the quality a little.
Why are images so large?
File size depends on three things: the number of pixels, the quality setting and the format. A phone photo can be 4000 pixels wide, far more than a web page needs. Lowering the quality setting removes detail the eye barely notices. Both together can shrink a photo to a fraction of its size.
JPG, PNG or WEBP?
- JPG: best for photographs. Small files, no transparency.
- PNG: best for logos, screenshots and graphics with sharp edges or transparency. Files are usually larger than JPG for photos.
- WEBP: a modern format that is often smaller than JPG or PNG at similar quality, and works in current browsers.
If you need to switch formats, use the Image Converter.
When quality alone is not enough
Compression only goes so far. If the file is still too big:
- Reduce the dimensions with the Image Resizer. A 4000-pixel photo shown at 800 pixels wastes most of its data.
- Aim for an exact size such as 50 KB or 100 KB with Resize Image in KB, handy for forms and exam portals.
- Remove the background of product shots and logos to simplify them, using Remove Background.
Why compress images for your website?
Smaller images load faster, which helps visitors on slow mobile connections and supports better search performance. If you run a shop, see our guide on white background product photos.
Is it safe to compress images online?
Many tools upload your pictures to a server. That matters for ID photos, documents and private pictures. The Image Compressor works inside your browser, so images never leave your device.
Tips
- Keep the original. Compression is not reversible, so save a copy before you compress.
- Compress once. Repeated compression keeps removing detail.
- Check before you send. Open the result and zoom in on faces and text.
- Batch your files. Select several images at once to save time.
Frequently asked questions
How do I compress an image without losing quality? Use a quality of about 70 to 80 percent. The difference is usually invisible, and the size drops a lot.
What quality should I use? Around 70 to 80 percent for most uses. Go higher for printing and lower for email.
Are my images uploaded? No. Compression runs in your browser.
Can I compress several images at once? Yes. Select more than one image and download them all.
Which formats are supported? JPG, PNG and WEBP.
Compress your images now. It is free, with no sign-up.