Does PNG compression preserve transparency?

Yes. OptimizePNG fully preserves alpha transparency in your PNG files. The compressed output keeps all transparency information intact, making it ideal for logos, icons, and web graphics.

What compression method does OptimizePNG use?

OptimizePNG uses pngquant, a highly regarded lossy PNG compressor. It converts 32-bit RGBA PNGs to 8-bit palette-based images with full alpha channel support, producing significantly smaller files that look nearly identical to the originals.

Compress PNG Images Online

Reduce PNG file sizes by up to 80% without losing visual quality. Batch upload up to 20 files and download them as a ZIP archive.

Drop your PNG files here

or click to select files manually

Up to 20 images - max 20 MB each - ZIP download for 3+ files

Drop files to compress

What is PNG Compression?

PNG (Portable Network Graphics) is the most widely used lossless image format on the web, but raw PNG files can be unnecessarily large. OptimizePNG applies smart lossy compression that reduces file sizes by up to 80% while keeping your images looking virtually identical to the originals. This means faster page loads, better Core Web Vitals scores, and lower bandwidth costs.

The optimized PNGs preserve full alpha transparency and are compatible with every modern browser, email client, and image editor. Whether you're a web developer optimizing assets, a designer preparing graphics, or a blogger compressing images for faster publishing - OptimizePNG handles it all with zero configuration.

How to Compress PNG Files

Drag and drop up to 20 PNG files into the upload area, or click "Browse Files" to select them from your computer
Each file is compressed automatically using pngquant - no settings needed
Download files individually, or get a single ZIP archive when you compress 3 or more files

Batch Compression with ZIP Download

Working with multiple images? OptimizePNG makes it easy. Upload up to 20 PNG files at once and they are all compressed simultaneously. When you have 3 or more completed files, the "Download ZIP" button appears - giving you a single archive with all your compressed images plus a summary file with compression details. This is perfect for batch-optimizing website assets, app icons, or entire image folders.

Why Compress PNG Files?

Large PNG files slow down your website and hurt search engine rankings. Google uses page speed as a ranking factor, and unoptimized images are one of the biggest performance bottlenecks. By compressing your PNGs, you can dramatically improve load times without sacrificing image quality. This is especially important for e-commerce sites, portfolios, and landing pages where every millisecond counts.

Compressed PNGs also reduce storage and bandwidth costs, making them ideal for mobile apps, email newsletters, and social media. Need to go further? You can convert PNG to WebP for even smaller file sizes, or convert PNG to JPG when you don't need transparency.

Related Image Tools

Need more than compression? Check out our free tools at ConvertICO.com: PNG to ICO Converter, Compress JPG, Compress GIF, Image Resizer, Image Upscaler, PNG to WebP, PNG to JPG, WebP to PNG, and JPG to PNG. Explore the full collection of Image Converters and Online Tools.

Frequently Asked Questions

OptimizePNG uses smart lossy compression that is virtually indistinguishable from the original. It reduces the number of colors intelligently while preserving the visual appearance. For most images, the difference is imperceptible even at close zoom levels.

Yes. Your uploaded files are processed on our server and automatically deleted within 1 hour. We do not store, share, or analyze your images. No account or signup is required - your privacy is our priority.

Each PNG file can be up to 20 MB in size. You can upload up to 20 files at once for batch compression. When you compress 3 or more files, you can download them all as a single ZIP archive. Need to compress larger files? Try our advanced image compressors at ConvertICO.com.

Yes. OptimizePNG supports batch compression of up to 20 PNG files simultaneously. Simply drag and drop all your files at once. When you have 3 or more compressed files, a "Download ZIP" button appears so you can get everything in a single archive - including a summary file with compression details.

Absolutely. OptimizePNG fully preserves alpha transparency in your PNG files. The compressed output maintains all transparency information, making it perfect for logos, icons, and web graphics. You can also convert your PNGs to ICO format while keeping transparency intact.

We use pngquant, a highly regarded lossy PNG compressor. It converts 32-bit RGBA PNGs to 8-bit palette-based images with alpha channel support, producing significantly smaller files that look nearly identical to the originals. If pngquant is unavailable, the tool falls back to ImageMagick optimization.

Typical results range from 40% to 80% file size reduction, depending on the image content. Screenshots and images with large flat-color areas tend to compress the most, while photographs with complex gradients may see smaller reductions. Even a 30% reduction can make a noticeable difference in page load times.

Use PNG when you need transparency or pixel-perfect graphics like logos and icons. Use JPG for photographs where small quality loss is acceptable. WebP offers the best of both worlds with smaller sizes and transparency support, but has slightly less universal compatibility. You can easily switch between formats using ConvertICO's image converters.