Download - Fortran 77 Compiler For Windows 10 64-bit Free

A native Windows port of GCC (GNU Compiler Collection), including gfortran. It generates true 64-bit Windows executables.

Create hello.f:

      PROGRAM HELLO
C     Standard Fortran 77 fixed format
      PRINT *, 'Hello, Fortran 77 on Windows 10 64-bit!'
      STOP
      END

Compile and run:

gfortran -std=legacy -o hello.exe hello.f
./hello.exe

Expected output:

 Hello, Fortran 77 on Windows 10 64-bit!

Best for: Ancient code that refuses to compile on modern compilers due to non-standard extensions or proprietary libraries. fortran 77 compiler for windows 10 64-bit free download

If you have a specific old compiler (like Microsoft Fortran 5.1) that you absolutely must use, you cannot run the installer directly on Windows 10 64-bit. You must use an emulator.

This method allows you to run truly vintage Fortran 77 environments, though it is significantly slower and less convenient than using GFortran. A native Windows port of GCC (GNU Compiler

GFortran recognizes .f as fixed-form, .f90 as free-form. If your file is named oldcode.for, simply rename it or use:

gfortran -x f77-cpp-input -std=f77 oldcode.for

Best for: Users who also need Unix tools, make, autotools. Compile and run: gfortran -std=legacy -o hello

Steps:

Now gfortran works in Command Prompt or PowerShell.