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

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