The Web Edition is a free version that supports a select range of Altera CPLD and medium-density FPGA families:
Do download "Quartus II 8.1" from random torrent sites or unverified third-party uploaders. These files are often infected with malware. Instead, use the official Intel legacy archive. Altera Quartus II 8.1 Web Edition -Windows- free download
Officially designed for Windows XP (32-bit) and Windows Vista . Users on Windows 10 or 11 may need to run the installer in "Compatibility Mode" or use a virtual machine running a legacy OS. The Web Edition is a free version that
Search for the verified 81_web_edition_setup.exe on the Internet Archive today, and relive the golden era of Altera programmable logic. Officially designed for Windows XP (32-bit) and Windows
For those determined to use Quartus II 8.1 Web Edition on Windows, the download process requires careful sourcing, a compatible OS (Windows 7 or a VM), and patience with driver and license configuration. When set up correctly, it remains a powerful, lightweight tool for small‑scale FPGA/CPLD development.
Download the latest supported version from Intel (Altera’s successor) FPGA software: