Compare software

OptiPNG vs Pngyu: catalog facts
OptiPNG	Pngyu
Free Free and open source under the zlib licence.	Free Free and distributed under the BSD license.
Windows, Command line	Windows, macOS
Lossless recompression of PNG files Converts BMP, GIF, PNM and TIFF to optimized PNG	Gives pngquant a graphical interface Pre-built binaries for Windows and macOS
Command line only, no graphical interface Lossless only, so savings are smaller than lossy tools	Handles PNG files only No pre-built Linux binary
Downloadable app	Downloadable app
Open source	Open source
License: Zlib	License: BSD-3-Clause
No account needed	No account needed
Works offline	Works offline
Official website Full listing and sources Checked October 2, 2026	Official website Full listing and sources Checked October 2, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.