Converting Latitude/Longitude to Easting/Northing

GeoCalc 4.20 is a 32-bit Windows application that uses seven-parameter transformations to convert ASCII coordinate data files between mapping systems. Pick from the extensive list or define your own. GeoCalc is distributed free of charge by GEOCOMP.

GeoCalc 4.20Introduction*Geocalc 4.20:*

  • Converts coordinate data files between most of the commonly-used mapping systems world-wide.
  • Uses seven-parameter transformations.
  • Has user-definable parameters allowing deployment anywhere in the world on almost any spheroid or mapping system.
  • Includes a large number of predefined mapping systems and spheroids.
  • Includes Geocentric Datum of Australia.
  • Compares geodesy of the same point in two different mapping systems.
  • Displays geographic, geocentric and projection coordinates of three dimensional points in any defined Mapping System.
  • Displays point scale factor and grid convergence.
  • Is a 32-bit Windows application.
  • Includes complete documentation in Help.
  • Is Copyright © Geocomp Systems.
  • Is downloadable free of charge from the web.
  • Is included on our Geocomp 10 CD.
  • Was released in November 1999.

Examples of supported mapping systems

  • Local Grid - chose your own
  • Mercator
  • Transverse Mercator - Australia (AMG, ISG, MGA), NZ, Germany, Canada, USA, Great Britain and Russia
  • Stereographic - Polar regions, Nederlands, Hungary, Poland
  • Lambert 1 Parallel - France, Belgium, Denmark
  • Lambert 2 Parallel - World Aeronautical Charts
  • Cassini-Soldner
  • Gnomic
  • New Zealand Map Grid
  • Skew Orthomorphic

Some of the predefined spheroids

  • WGS84
  • WGS72
  • WGS99
  • Australian GDA94/MGA94
  • Bessel 1841
  • Malaysia Kertau 1948 Everest Modified
  • North American Datum 1983

File FormatsGeocalc supports a wide range of ASCII text coordinate formats for import and export. Coordinates can be expressed as Latitudes and Longitudes, Easting and Northing or X,Y,Z.

The following coordinate file formats are predefined:

  • Geocomp Spatial Data System (.PTS & .STR)
  • Geocomp Field File (.FLD)
  • GeoNav Coast File (.CST)
  • UKOOA P1/90
  • X Y Z

GeoCalc 4.20 is an ideal companion for Geocomp, GeoNav, or any other point-based spatial data system.

If you require NTv2 grid database transformations, consider our Trimble Terramodel with GCCOORD.

Download Geocalc 4.20

  • Download gcalc420.exe (2 MB).
  • Uninstall any previous versions of GeoCalc using Control Panel.
  • Run the self-extracting gcalc420.exe.
  • Run C:\Program Files\GeoCalc\Install\setup.exe.
  • Select GeoCalc from the Windows Start Menu.
  • See GeoCalc Help for instructions.


Tips and Tricks

  1. Erosion Control Banks & Waterway
  2. Drainage Design Solutions of Different Topographies
  3. Runoff vs Slope
  4. Trimble Field Level II Do Not Show the .gps File
  5. Minimum Recommended Smoothing Distance For Export To Trimble Field Level 2
  6. GPS Base Station Setup For Best Vertical Accuracy
  7. How to Survey with Trimble FMX
  8. How Easy is OptiSurface to Use for the Average Farmer?
  9. Balancing Earthworks in the Field
  10. Landform Design Slopes and Smoothing
  11. Export Proposed Topography to AutoCAD
  12. Surface Irrigation Designs with Variable Slope
  13. OptiSurface Designer Import and Export Format
  14. Importing Multiple Survey Files to OSD
  15. Can Drone Or LIDAR Surveys be used with OptiSurface?
  16. Calculation Grid Spacing and Export Grid Spacing
  17. How to Survey a Field for Landforming Design
  18. Loading .gps File in FmX
  19. Designing a Field in Sections
  20. Using an Old OSD File versus a New Survey
  21. No Master Benchmark on Imported Survey File
  22. Displaying Secondary Benchmarks
  23. Import Error for xyz File Due to Encoding Format
  24. OptiSurface4D: Bounded By Ridges
  25. Can OptiSurface handle curved rows in Drainage Analysis & Runoff Analysis?
  26. Reverse Grades to Main Slope
  27. Measuring Culvert Invert Level
  28. Surveying a 1000-Ha Field
  29. GPS Coordinate System Check
  30. Does A Normal UTM Zone Coordinate Need To Be Trimmed To x Digits?
  31. Can You Import Data Directly From GPS System?
  32. Converting Latitude/Longitude to Easting/Northing
  33. Surveying With Any GPS Equipment and Exporting to a gps file for the Trimble FMX
  34. DGPS Post Treating System with 5cm Precision For Landforming
  35. Exporting to Trimble FMX Field Level
  36. Can I Survey with a GPS System on an ATV?
  37. Standard NMEA GPGGA txt File to Import into OptiSurface Designer
  38. 900 Acres: Cut that large survey down.
  39. Export Options for Data Layers
  40. Import Two or More Survey Files to Reach Minimum Area
  41. Different Row Slope Directions In One Field
  42. Does OptiSurface allow for multiple grade breaks per design, taildrains roads, pads etc?
  43. Can I View DTM/Topography In Plan View Or 3D Type View When Doing A Design?
  44. Adjust the Bands in the Legend
  45. Design for a 1000-Ha Field
  46. Would It Be Possible That The Numbers In The Boundary Zone Appear In The New Subzone Created?
  47. Grade Of Best Fit And Splitting The Field Into Boundaries
  48. Acceptable Minimum Slopes
  49. Incorrect Area in OptiSurface
  50. Valley Subzone Not Behaving as Expected
  51. Difference Between Breaklines And Subzones
  52. Alignment of Furrow/Bed Direction with OptiSurface Design Mainslope Direction
  53. Subzones Settings Over Ride Boundary Zone Settings
  54. Printing the Maps
  55. Print Size

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