GMT is released under the GNU General Public License

Note: current version is GMT-3.3.4. Also see the ERRATA page.

Version 3.3.4 was officially announced on March 20, 2000. Click here to read the release announcements.

GMT is a free, public-domain collection of ~60 UNIX tools that allow users to manipulate (x,y) and (x,y,z) data sets (including filtering, trend fitting, gridding, projecting, etc.) and produce Encapsulated PostScript File (EPS) illustrations ranging from simple x-y plots through contour maps to artificially illuminated surfaces and 3-D perspective views in black and white, gray tone, hachure patterns, and 24-bit color. GMT supports 25 common map projections plus linear, log, and power scaling, and comes with support data such as coastlines, rivers, and political boundaries.

GMT is developed and maintained by Paul Wessel and Walter H. F. Smith. 

Where is GMT used?

GMT is used all over the world. The yellow dots show the location of individuals at 700+ institutions who have installed GMT, representing about 6000 GMT users. To add your dot, fill out the registration form.

Online GMT Services

GMT Examples

Cannot find the answer to a question in the documentation?

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There is a second mailinglist that is only used by the GMT developers to broadcast infrequent messages regarding bug fixes and updates. Users cannot post to this mailinglist. To stay informed of new developments, send mail to the listserver replacing gmthelp with gmtgroup in the message example above. Note: the GMT developers monitor both lists and are aware of all submissions allthough they may not respond personally to each message.

 Occacionally, a frustrated new GMT user will convince him/herself that their work is so important that they are justified in digging up our phone numbers and calling us directly to get personal attention to their problem. Please don't even think about doing this unless you are prepared to pay our standard consulting fee of USD 200 per hour. 

Availability of GMT source code

Obtaining and Installing GMT

1. UNIX or LINUX: Because of the size of the archives we suggest you verify that you have bzip2 on your system. If not, it is worth installing (executables for most platforms are available) since *.bz2 files are much smaller than the *.gz files. For instance, the entire GMT package is ~50 Mb with bzip2 and 75 Mb with gzip.
   1. Have csh or tcsh. Obtain and install GMT by interacting with the INSTALL FORM on the web. Follow instructions there to obtain an csh install-script and a customized install parameter file.
   2. Only sh or bash. If you cannot use csh/tcsh, you must do the typical manual install by ftping the files, untar, run configure, make etc. Read the README file for the required steps. For manual install you must also manually get and install the Unidata netCDF library, version 3.4 or higher, which GMT requries. For your convenience, this library is also available from the GMT ftp sites.

2. WINDOWS:
   1. DOS scripts rule. All the archives are also available as *.zip files. In addition, two extra files can be found: GMT_exe.zip contains main GMT executables, and GMT_suppl_exe.zip contains executables for the supplements. Note that many of the DOS example scripts utilize GNU awk; the WIN32 executable gawk has therefore been placed on all ftp sites. A precompiled netCDF library for Windows is also available, and needed for GMT to compile and run (even if you only get the executables). For your convenience, this library is also available from the GMT ftp sites.
   2. DOS scripts suck, part I. Because you cannot get much done with DOS batch jobs, we strongly recommend that you install Cygwin, a free Unix emulation package for Windows. Cygwin lets you open a bash command window and run bash shell scripts and comes with a suite of standard Unix tools. You would then install GMT manually as under 1.2 above. If you don't like bash then Cygnus (now RedHat) sells a commercial version that has csh.
   3. DOS scripts suck, part II. If you run Windows NT, you can get access to csh command windows by installing the commercial product Interix, a Unix environment for Windows. Interix lets you install GMT automatically as under 1.1 above. Recently, Interix was assimilated by the Borg from the planet Redmond.

3. OS/2: GMT has been ported to OS/2. For information and precompiled executables, see Allen Cogbill's GMT OS/2 page.

4. MacIntosh:
   1. Running Linux. If you run Linux on your Mac, follow the steps above for automatic install under UNIX or LINUX (1.1).
   2. Running MacOS X Server. GMT installs and runs under MacOS X Server which is Unix-based (follow instructions for UNIX/Linux in 1.1).
   3. Running MacOS 8 or 9. GMT does not run directly under MacOS 9 or earlier. However, you can run GMT using the commercial Machten Unix emulation package. When Machten is installed, GMT can be installed as under 1.1 above.

GMT master and mirror sites

1. SOEST, Dept of Geology & Geophysics, Honolulu, Hawaii, USA. Serving the Pacific Rim
2. NOAA, Lab for Satellite Altimetry, Silver Spring, Maryland, USA. Serving North America
3. IAG-USP, Dept of Geophysics, Sao Paulo, Brazil. Serving South America
4. IFG, Institute for Geology, Oslo, Norway. Serving Europe
5. Charles Sturt U, Albury, Australia. Serving Australia
6. ISV, Sapporo, Japan. Serving Asia

Post-Installation Notes

• The latest compressed tar archives for version 3.3.4 were created March 20, 2000. See the list of known bugs since the creation of the archive - use this information to temporarily fix these problems.
• The latest version may have caused a few cases of backward incompability with previous versions, so you may need to modify your custom scripts.
• You can also check out the latest news about programs and useful scripts added to the ftp site since the release of the current GMT version. 

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An illuminated view of the world.

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