http://www.mbr-pwrc.usgs.gov/software/g77.html

Free FORTRAN Compiler

g77 is a free Fortran 77 compiler from the Free Software Foundataion (FSF). For info on G77, now integrated into the GNU Compiler Collection (GCC), see the online g77 documentation

To install the Windows version of the compiler, you will need to download the following file:

Next, unzip this file onto the root folder of drive C:.

Before running the compiler, you will need to run the g77setup.bat file in the c:\g77 folder. This sets up the path and an environment variable necessary for the compiler. This needs to be done each time you open an MSDOS window. To aviod this, you can copy the text from this file and append it to your autoexec.bat file (then reboot).

 

http://software.intel.com/en-us/articles/non-commercial-software-download/

                Free for non-commercial, non-academic users

http://www.g95.org/downloads.shtml

This compiler is due to Andy Vaught.  He describes its origin in the G95 manual. 

 

g95-MinGW-41.exe

·                     This build is similar to the g95-MinGW.exe package

·                     Sets the G95_LIBRARY_PATH environment variable

·                     Built against gcc-4.1.2

·                     Will not interfere with gcc and gfortran

·                     Self-extracting installer

·                     Works on Windows Vista/XP/2000

·                     Use a CMD or DOS window, g95 is a command-line compiler

·                     Installs all files needed to compile programs for Windows

·                     Optionally installs g95 in an existing MinGW/Msys filesystem

·                     MinGW/Msys offer unix-style tools such as make, gdb

·                     MinGW provides gcc

·                     Download from: http://ftp.g95.org/g95-MinGW-41.exe

g95

 

Has both linux and windows binaries

http://gcc.gnu.org/wiki/GFortranBinaries

                This is from the Free Software Foundation.

Windows

Three kinds of packages are provided for Windows users: cygwin (for cygwin users) and mingw/"native Windows" (for people who do not use cygwin). If in doubt, or if you don't know what cygwin and mingw are, the package for you is the "native Windows" package!

Note: The official MinGW and Cygwin project sites also offer GCC/gfortran builds - though they are older (4.3 in November 2008); see MinGW and Cygwin (GCC4 packages).

MacOS

gfortran is available as a nice Apple-style installer for MacOS X Tiger (10.4) and Leopard (10.5) users. It is easy to install. Detailed instructions are here. Both PowerPC and Intel compilers are provided:

There's also an Xcode plugin for gfortran which uses the binaries compiled by Gaurav Khanna.

GNU/Linux

Most Linux distributions offer gfortran packages (including 4.3.0) For those of you who wish to try the latest gfortran (under development), we offer regular builds for the 32bit x86 (ia32, i386, x86-32) and the 64bit x86-64 (AMD64, Intel em64t, Intel64) Linux systems.