PNG
Portable Network Graphics
MIME type: image/png
PNG is a lossless raster image format that supports transparency. It was created as an improved, non-patented replacement for GIF and is the most widely used lossless image format on the web.
Advantages
- +Lossless compression — no quality loss
- +Full alpha transparency support
- +Wide browser and software support
- +Good for graphics, logos, screenshots
Limitations
- -Larger file sizes than JPEG for photographs
- -No animation support (use APNG or GIF)
- -Not ideal for print (use TIFF or PDF)
- -No EXIF metadata support
Common Use Cases
Technical Details
PNG uses DEFLATE compression (the same algorithm as ZIP files) applied to filtered image data. It supports 8-bit and 16-bit color depths, grayscale, indexed color, and full-color RGB/RGBA. The format stores images in chunks (IHDR, IDAT, IEND) and includes a CRC checksum for data integrity. PNG files begin with an 8-byte signature: 137 80 78 71 13 10 26 10.
Frequently Asked Questions
What is a PNG file?
PNG (Portable Network Graphics) is a lossless image format that supports transparency. It's ideal for web graphics, logos, and screenshots where you need crisp edges without quality loss.
PNG vs JPG — which should I use?
Use PNG for graphics with text, logos, screenshots, or images needing transparency. Use JPG for photographs and complex images where smaller file size matters more than perfect quality.
How do I make a PNG file smaller?
Use PNG compression tools that optimize the DEFLATE compression and reduce the color palette. Tools like BriskTool's image compressor can reduce PNG files by 60-80% with minimal visible quality loss.