This page is for a photograph containing several people that you want to send in a chat. A WhatsApp group icon is a different task: it needs a small square source and a composition that survives a circular view. For that kind of image, use the DP size tool and check the icon preview inside WhatsApp.
For a shared group photograph, keeping the whole frame is often more important than filling a standard rectangle. This page fits the source inside our 2048×2048 pixel box without forcing a crop. A wide team photo remains wide. A vertical family portrait remains vertical. The export uses a 90% JPEG starting setting and light edge sharpening, with no fixed file-size target.
Begin with the original photograph. A picture recovered from a previous group chat may already have lost the small faces and clothing detail that matter here. Enlarging that file cannot restore the capture. Before exporting, also check whether every person is comfortable with the intended sharing. The compressor prepares a file locally; you decide where that photograph goes and who receives it.