What is the KitBox Image Compressor?
The KitBox Image Compressor is a free online tool that makes your pictures smaller without making them look bad. Smaller images load faster on websites, take less space on your phone, and are easier to send by email or upload to forms with size limits. It works with JPG, PNG and WebP files, and everything happens inside your own browser, so your images are never sent to a server.
How to compress an image online
- Choose your images. Click the upload box or drag your files into it. You can add up to 30 at once.
- Set the quality. 70 to 80 is a good starting point for most photos.
- Pick a format and size. Keep the original format, or choose WebP for the smallest files. You can also set a maximum width.
- Click "Compress Images". The tool shows each file's size before and after.
- Download. Save images one by one, or all together as a ZIP file.
Why use this image compressor?
- Private by design. Your images stay on your device. Nothing is uploaded.
- Free, with no sign-up. No account, no watermark and no daily limit.
- Batch compression. Handle many images at once and download them as a ZIP.
- Full control. Choose the quality, the output format and the maximum width.
- Clear results. See the exact file size saved for every image.
JPG, PNG or WebP: which should you choose?
- JPG is best for photos. It gives small files and works everywhere.
- PNG is best for logos, screenshots and images that need a transparent background. It keeps every detail but files can be large.
- WebP is a modern format that is usually smaller than both JPG and PNG, and it is supported by all current browsers.
Note: images with a transparent background turn white if you convert them to JPG. Use PNG or WebP to keep transparency.
Tips for the best results
- Reducing the width saves the most space. A phone photo is often far larger than any screen needs.
- Start at quality 75, then lower it step by step until you notice a difference.
- Keep your original files. Compression is a one-way change, so save the compressed copy under a new name.
- For website images, 1200 to 1920 px wide is usually plenty.
Frequently asked questions
Is the Image Compressor free?
Yes. It is completely free, with no sign-up, no watermark and no daily limit.
Are my images uploaded to a server?
No. Compression happens inside your own browser, so your images never leave your device.
Which image types are supported?
You can compress JPG, PNG and WebP images. You can also convert between these formats while compressing.
What quality setting should I use?
A quality of 70 to 80 usually gives a much smaller file with no visible difference. Go lower for the smallest size, or higher if you need the best possible detail.
Why did my PNG not get much smaller?
PNG is a lossless format, so the quality setting does not change its size. To save much more space, convert the image to WebP or JPG, or reduce its width.
Can I compress many images at once?
Yes. You can select up to 30 images at a time and download them one by one or all together as a ZIP file.
More free image tools
- All image tools
- Text Highlighter – highlight words in images and PDFs
- Image Resizer
- Image to WebP