Go to the MinGW-w64 website or use a distribution like winlibs.com , which provides standalone "zip" versions that don't require an installer.
This is a heavy download (several gigabytes) and is intended for professional-grade performance. It is fully 64-bit compatible and handles F77 code with ease. How to Compile Your First F77 Program
For those needing maximum performance, Intel renamed their famous "Intel Fortran Compiler" to and made it free as part of the oneAPI toolkits. fortran 77 compiler for windows 10 64-bit free download
It is technically a paid product, but it offers a fully functional free trial and a "Legacy" version that often suits F77 needs perfectly. It is the closest experience to the old "PowerStation" or "Compaq" compilers of the 90s. 3. Silverfrost FTN95
It includes a debugger, a development environment, and handles all the "path" setup for you. Go to the MinGW-w64 website or use a
They offer a free Personal Edition which displays a small banner when you run your programs, but otherwise provides a full-featured F77/F90/F5 compiler for 64-bit Windows.
F77 uses "Fixed Form" (where columns matter). Ensure your file extension is .f or .for so the compiler knows to use F77 rules. How to Compile Your First F77 Program For
Even if your Windows is 64-bit, a 32-bit compiler will still work. However, if you are handling massive datasets, ensure you download the x86_64 version of MinGW.
Visit the Silverfrost website to download the "FTN95: Fortran for Windows" package. 4. Intel® oneAPI IoT Toolkit (High Performance)