| Price from | — | Free |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | — | Yes |
| Windows | Yes | — |
| macOS | Yes | — |
| Linux | Yes | — |
| API | — | Yes |
| Plans published | 0 | 5 |
| Spec score · Image Compression Software | 6.9 (#85) | 8.7 (#10) |
| Formats | It searches directories recursively for PNG, APNG, JPEG, GIF, WebP and SVG files, with extensions in either case. | The API accepts JPEG, PNG, WebP, AVIF, GIF, TIFF, JXL, and SVG; GIF and TIFF convert to PNG, while SVG stays SVG. |
| Maker | The GitHub profile identifies the maker as Kamil Doroszewicz and lists Poland as the location. | The privacy policy identifies the controller as Roman Klymenko, Creative company ARTEX group, registered in Radom, Poland. |
| Purpose | losslessly is a command-line image optimizer that recompresses PNG, JPEG, GIF and WebP files and minifies SVG markup. | Pixozip provides an HTTP API and web dashboard for optimizing uploaded image files. |