Windows 11 has surpassed 1 billion users worldwide, achieving this milestone 1,576 days after its public launch on October 5, 2021. In comparison, Windows 10 reached the same mark in 1,692 days after its launch on July 29, 2015. Windows 11 is a free upgrade for Windows 10 users, but its higher system requirements have made many Windows 10 PCs ineligible for the upgrade. Currently, between 50 and 55 percent of Windows PCs globally are using Windows 11, while approximately 40 to 45 percent are still on Windows 10. Estimates suggest that hundreds of millions of devices continue to run Windows 10, even after its official end-of-support date last October. By late 2025, around 1 billion active Windows 10 PCs are expected to still be in use, with about 500 million unable to upgrade due to hardware limitations.