The 0.7.5 version of OptiPNG for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The application lies within Design & Photo Tools, more precisely Viewers & Editors. This free software for Mac OS X was originally designed by Cosmin Truta.
From the developer:
OptiPNG is a PNG optimizer that recompresses image files to a smaller size, without losing any information. This program also converts external formats (BMP, GIF, PNM, and TIFF) to optimized PNG, and performs PNG integrity checks and corrections where needed.
You may want to check out more software for Mac, such as PNG Compressor or PNGshrink, which might be similar to OptiPNG.
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