Imagator might be a bit more popular than PngOptimizer. We know about 1 link to it since March 2021 and only 1 link to PngOptimizer. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Personally, I like the psydk PNGOptimizer https://psydk.org/pngoptimizer for PNG files and FileOptimizer for JPEG files. The latter will work on all kinds of files but is exceptionally slow on PNG files. You can mess with the settings so it doesn't take so long but I don't bother. Source: about 2 years ago
Imgator: Compress, convert, edit and resize your images\ (0 comments). Source: almost 2 years ago
TinyPNG - Make your website faster and save bandwidth. TinyPNG optimizes your PNG images by 50-80% while preserving full transparency!
Optimage - Advanced image optimization tool
ImageOptim - Faster web pages and apps.
CompressImage.io - Compress image online within seconds. The Fastest Jpg compress and png compress engine right in your browser.
pngquant - command-line utility and library for lossy compression of PNG images
Shrink.media - Reduce the file size of your images by smartly compressing & reducing dimensions.