Image Compressor
How to Use
- Select or drop an image file (JPEG, PNG, or WebP).
- Adjust the quality slider — lower values produce smaller files.
- Set maximum width and height to resize the image if needed.
- Choose the output format (JPEG, PNG, or WebP).
- Click Compress, then download the result.
What Is Image Compression?
Image compression reduces file size by removing redundant data. Lossy compression (JPEG, WebP) discards some visual detail for much smaller files, while lossless compression (PNG) preserves every pixel. This tool uses the Canvas API built into your browser to re-encode images at your chosen quality level.
Common Use Cases
- Optimizing images for websites and blogs to improve page load speed.
- Reducing photo file size before uploading to social media or email.
- Converting between image formats (e.g., PNG to WebP for better compression).
- Resizing images for thumbnails, avatars, or profile pictures.
- Preparing images for mobile apps where bandwidth is limited.
Tips
- JPEG quality 60-80 provides a good balance between file size and visual quality.
- WebP typically achieves 25-35% smaller files than JPEG at the same visual quality.
- PNG is best for images with text, sharp edges, or transparency.
- Reducing dimensions has the biggest impact on file size — try halving the width and height.
- Preview the compressed image before downloading to check for visible artifacts.
Privacy
All image processing happens entirely in your browser using the Canvas API. Your images are never uploaded to any server. No data leaves your device.
FAQ
Are my images uploaded to a server when I compress them?
No. Every image is decoded and re-encoded entirely in your browser using the Canvas API. Nothing is uploaded — your photos and private images never leave your device.
What is the difference between lowering quality and reducing dimensions?
Quality controls how much visual detail lossy formats (JPEG, WebP) discard, while dimensions change the actual pixel count. Reducing width and height usually has the biggest impact on file size, and you can combine both.
Which input and output formats are supported?
You can load JPEG, PNG, or WebP and output to any of those three. The quality slider only affects the lossy formats (JPEG and WebP); PNG is lossless, so its quality is preserved regardless of the slider.
Why doesn't PNG shrink much when I lower the quality?
PNG is a lossless format, so the quality slider does not apply to it the way it does for JPEG or WebP. To shrink a PNG, reduce its dimensions or convert it to WebP, which is typically 25–35% smaller at the same visual quality.
Is there a file size limit?
Processing is bounded by your device's memory rather than a fixed server limit, since everything runs locally. Very large images may take a moment; reducing the max width and height first keeps memory use and processing time manageable.