お手軽PNGオプティマイザー/Easy PNG Optimizer

This tool reduces PNG file size through removal of unnecessary information, re-encoding with unnecessary data removal, and color reduction.
According to specifications, APNG is not supported.
Multiple file processing is supported (output as ZIP). Comparison before and after processing is also possible.

Processing is completed entirely within the browser with no external communication. Supports Japanese and English, using LocalStorage only for language setting persistence. If cache accumulates too much, performance may slow down, so please clear it regularly.