Compress PNG Online – Free PNG Compressor
Reduce PNG file size directly in your browser while preserving transparency and maintaining strong visual quality. Upload, compress, compare, and download optimized PNG images without sending files to a server. Or drag & drop images here PNG files only · Up to 20 files per batch · Up to 20 MB eachWhy Use CompressIMG PNG Compressor?
Local Browser Processing
Your PNG files are processed locally in your browser and are not uploaded to our server.
Batch PNG Compression
Compress up to 20 PNG files in one batch, with files up to 20 MB each.
Preserve PNG Transparency
Transparent and partially transparent areas remain supported in the compressed PNG output.
Before-and-After Preview
Compare the original and compressed images before downloading the result.
How to Compress PNG Online
Compress PNG files directly in your browser while preserving transparency. Upload PNG images, adjust quality, compare results, and download individual PNG files or a ZIP for multiple images.
Upload PNG Files
Choose up to 20 PNG files from your device or drag and drop them onto the page. Each file can be up to 20 MB.
Adjust PNG Quality
Use a higher value to preserve more colors or a lower value to create a smaller file. At 100%, the tool does not intentionally reduce the color palette.
100% does not intentionally reduce the color palette.
Start Compression
Click "Start Compression" to process the PNG files locally in your browser.
Compare and Download
Compare the original and compressed PNG, then download each result or download multiple processed files.
What Is PNG Compression?
PNG compression reduces the file size of a PNG image while preserving transparent areas and important visual details. PNG is commonly used for logos, icons, screenshots, interface graphics, diagrams, and other images that require sharp edges or transparency.
The final file size depends on the image dimensions, number of colors, transparency, and the selected quality setting. Images with fewer colors and large areas of similar color usually compress more effectively than photo-like PNG images.
How CompressIMG Compresses PNG Files
CompressIMG uses two methods to optimize PNG images.
At 100% quality, the tool re-encodes the PNG without intentionally reducing its color palette. This setting is designed to preserve the visible colors and transparency of typical PNG images.
At lower quality settings, the tool may reduce the maximum number of colors in the image. A smaller color palette can produce a significantly smaller PNG file, although some colors may change slightly.
If palette compression does not create a smaller file, CompressIMG automatically tries re-encoding the PNG without intentionally reducing its color palette. If neither method reduces the file size, the original file is returned and marked as already optimized.
All processing happens locally in your browser. Your PNG files are not uploaded to the CompressIMG server.
When Should You Compress PNG Images?
PNG compression is useful when you need to reduce the size of:
Logos and Icons
Compress transparent logos and icons while keeping their transparent backgrounds.
Website Screenshots
Reduce the size of screenshots, interface graphics, and images containing text before adding them to a website.
App and UI Assets
Optimize buttons, interface elements, diagrams, and other graphics used in websites or applications.
Email and File Sharing
Create smaller PNG files that are easier to upload, store, attach to emails, and share online.
Documents and Presentations
Reduce the size of charts, diagrams, screenshots, and transparent graphics used in documents or presentations.
Photo-like PNG images with many colors may remain relatively large after compression. For photographs, JPG, WebP, or AVIF may produce a smaller file.
Real PNG Compression Results
Compression results vary depending on the image dimensions, color complexity, transparency, and selected quality setting.
The examples below are based on real PNG files processed by CompressIMG at a 75% quality setting.
| Image Type | Dimensions | Original File Size | Compressed File Size | Reduction | Quality Setting |
|---|---|---|---|---|---|
| Transparent logo | 1024 × 1024 px | 722.7 KB | 350.2 KB | 52% | 75% |
| UI screenshot | 3360 × 1880 px | 725.2 KB | 172.7 KB | 76% | 75% |
| PNG illustration | 1408 × 768 px | 2.81 MB | 252.1 KB | 91% | 75% |
Some PNG files may already be highly optimized. In that case, CompressIMG returns the original file rather than creating a larger result.
PNG vs JPG vs WebP vs AVIF
Different image formats are suitable for different types of content.
| Format | Best For | Transparency | Typical File Size |
|---|---|---|---|
| PNG | Logos, screenshots, icons, and UI graphics | Yes | Larger |
| JPG | Photos and complex images | No | Small |
| WebP | General website images | Yes | Smaller |
| AVIF | Modern web images and stronger compression | Yes | Very small |
Use PNG when transparency, sharp edges, and clear text are important. Use JPG for photographs, WebP for general website images, and AVIF when stronger file-size reduction is the main priority.
Frequently Asked Questions
Is this PNG compressor free?
You can compress PNG files without paying or creating an account. You can process up to 20 PNG files per batch, with a maximum file size of 20 MB per image.
Does PNG compression affect image quality?
At 100% quality, CompressIMG re-encodes the PNG without intentionally reducing its color palette. Lower settings may reduce the color palette and cause small visual changes while producing a smaller file.
Will PNG transparency be preserved?
Yes. Transparent and partially transparent areas remain supported in the compressed PNG output.
Why is my compressed PNG not smaller?
The image may already be optimized, or its colors and pixel data may not compress efficiently. In that case, CompressIMG returns the original file instead of producing a larger result.
Are my PNG files uploaded to a server?
No. PNG decoding, compression, comparison, and download processing happen locally in your browser. Your image files are not sent to the CompressIMG server.
Can I compress multiple PNG files?
Yes. You can process up to 20 PNG files in the same batch. Each file can be up to 20 MB.
What does the 100% quality setting mean?
At 100%, CompressIMG re-encodes the PNG without intentionally reducing its color palette. Lower values may use fewer colors to produce a smaller file.
Can I upload JPG, WebP, or AVIF files on this page?
No. This page accepts PNG files only. Use the CompressIMG multi-format tool to compress or convert JPG, PNG, WebP, and AVIF images.
PNG and Image Optimization Guides
Learn how to reduce PNG file size, optimize images for websites, and choose the right image format.
Compress Other Image Formats
Need to process a different image format?
Compress JPG Images
Reduce the size of JPG and JPEG photos for websites, email, and file sharing.
Compress JPGCompress WebP Images
Optimize WebP images while maintaining strong visual quality.
Compress WebPCompress and Convert Multiple Formats
Use the CompressIMG multi-format tool to compress or convert PNG, JPG, WebP, and AVIF images.
Compress Images Online