Please read before downloading. Important Critical Issue Notice for all Quartus II software version 12.1 service pack 1 users.
Select a previous version of Quartus II:
You may be exposed to a vulnerability issue if you have installed or plan to install Quartus prime/Quartus II software from v11.0 to v18.0 to a location with space(s) in the path. See this KDB solution for more details.
If you do not have Internet access or if you require a DVD, you can download and use the DVD ISO file to create your own installation DVD for installing Altera's software and device support. You must first install the Altera Complete Design Suite (ACDS) software (Windows or Linux version) before you install the ACDS Devices software. You must install both the ACDS software (Windows or Linux version) and the ACDS Devices software.