Compress PNG

An Online PNG Optimizer is a specialized tool designed to process and potentially reduce the file size of your PNG (Portable Network Graphics) image files. PNG is a lossless format, meaning it doesn't lose quality with compression. This tool re-processes your PNGs, which can help by stripping unnecessary metadata or by re-encoding them using the browser's standard PNG encoder. This can sometimes result in a smaller file size, especially for unoptimized PNGs, while always maintaining visual quality.

Zenfied's PNG Optimizer operates entirely within your web browser (client-side). This means your PNG files are never uploaded to our servers, ensuring your data remains private and the process is fast and secure.

1. Add Your PNG Images: Drag and drop your PNG image files (.png) onto the designated area, or click the area to browse and select files from your computer. You can upload multiple PNG images at once.
2. Optimize Images: Once your images are added, simply click the "Compress Images!" button. The tool will automatically process each PNG.
3. Download Results: The tool will re-encode the PNG images directly in your browser. After completion, you'll see a summary of the results (original vs. new size). You can then download each optimized PNG image individually or all of them as a ZIP file (if multiple images were processed). The output will always be a PNG file.
4. Clear or Optimize More: Use the "Clear All" button to remove all uploaded files and start fresh, or "Compress More Images" to return to the upload screen.

• Secure & Private: All PNG processing happens in your browser. Your files are never uploaded.
• Client-Side Processing: Utilizes your device's power for fast PNG optimization.
• Easy to Use: Simple drag-and-drop interface for quick PNG processing.
• Batch Processing: Optimize multiple PNG images simultaneously.
• Specialized for PNGs: Works exclusively with .png input images.
• Lossless Re-encoding: Processes PNGs without any loss of visual quality.
• Potential Metadata Stripping: Can help remove unnecessary metadata, contributing to smaller file sizes.
• Completely Free: Optimize your PNGs without hidden costs or subscriptions.
• No Installation Needed: Works directly in modern web browsers.
• Direct Image Download: Get your optimized PNG files individually or as a ZIP archive.
• Optimization Details: See the original and new file size, and the percentage change for each image.

Our PNG Optimizer uses the browser's built-in Canvas API to process your PNG images. Here’s a simplified explanation of what happens:

1. When you upload a PNG, the tool loads it into the browser.
2. The image is then "drawn" onto a digital canvas in your browser's memory. This step effectively decodes the PNG image data.
3. Finally, the content of this canvas is re-exported as a new PNG file using the browser's standard PNG encoder (canvas.toBlob('image/png')).

Lossless Re-encoding: This entire process is lossless concerning the visual pixel data. The image you get out will look identical to the one you put in.

Why File Size Might Change:

• Potential Reduction:
  • Metadata Stripping: The canvas re-encoding process typically strips most non-essential metadata (like camera information, software notes, color profiles that might not be strictly needed for web display). If your original PNG was bloated with such metadata, you'll likely see a file size reduction.
  • Re-encoding Unoptimized PNGs: If your original PNG was saved with minimal or no compression (e.g., a raw screenshot or a basic save from some software), the browser's standard PNG encoder might apply more effective lossless compression, leading to a smaller file.
• Potential Increase (or No Significant Change):
  • Already Highly Optimized: If your original PNG was already heavily optimized using specialized tools (like OptiPNG, PNGCrush, TinyPNG, etc.) that employ advanced lossless compression techniques (e.g., palette optimization, Zopfli compression), re-saving it through the browser's standard canvas-to-PNG process might result in a slightly larger file. The browser's encoder is generally good but may not achieve the same level of aggressive optimization as dedicated tools.
  • Minimal Metadata: If your original PNG had very little metadata and was already reasonably well-compressed, the change in file size might be negligible.

Essentially, this tool provides a way to standardize your PNGs using the browser's encoder and strip common metadata, which can be beneficial for consistency and, in many cases, file size. It does not perform the more advanced, aggressive lossless compressions that some standalone PNG optimizers do.

• Maintain Quality: Guarantees no loss of visual quality as PNG is a lossless format and the process is a lossless re-encode.
• Potential Size Reduction: Can reduce file sizes for unoptimized PNGs or those containing extensive metadata.
• Standardize PNGs: Ensures your PNGs are processed through a standard encoder, which can improve consistency.
• Privacy Focused: Client-side processing means your images never leave your computer.
• Faster Website Loading (Potentially): If file sizes are reduced, web pages can load quicker.
• Save Storage Space (Potentially): Smaller files mean less disk space used.