Compress PNG Online Free
Steps
Open FastEdit
Go to app.fastedit.net. No installation or account needed: the editor runs entirely in your browser using WebAssembly.
Load your PNG
Drag and drop your PNG file onto the editor, or click to browse. The file stays on your device, and nothing is uploaded to any server.
Choose compression settings
For lossless compression, FastEdit applies OxiPNG to re-encode your PNG with optimal filtering and compression. For much larger savings, enable color quantization to reduce the palette while preserving visual quality.
Use fit-to-size if needed
If you need to hit a specific file size target, enable fit-to-size and enter your limit. FastEdit automatically adjusts quality parameters to meet the target.
Preview and export
Compare the original and compressed versions side by side. When satisfied, click Export to download your optimized PNG.
Benefits
- Lossless OxiPNG optimization reduces file size 10-30% without changing a single pixel.
- Color quantization can cut PNG size by 60-80% with minimal visible difference.
- Transparency is fully preserved, no flattening or background color applied.
- No file size limits or daily caps. Compress as many PNGs as you need.
- Works offline once the page is loaded, no internet connection required after initial load.
Compression Tips
- PNG compression is always lossless at the encoding level: you will never lose quality from re-encoding alone, only metadata and optimization savings.
- Color quantization (reducing from millions of colors to 256 or fewer) is the most effective way to shrink PNGs. Most screenshots and UI graphics look identical after quantization.
- Screenshots and UI graphics compress especially well as PNG because they have large flat-color regions.
- If you do not need transparency, consider converting to WebP or JPEG for even smaller files.
- PNG uses a built-in compression algorithm called DEFLATE. OxiPNG finds better parameters for this algorithm than most tools use by default, squeezing out extra savings without any quality loss.
Free. No upload. No watermark. No account. No limits.
Compress Now, Free