GPS is used increasingly and commonly in the last past year in all aspect of live. But the height informa-
tion in GPS is not the actual height. To convert it to actual height is needed the geoid undulation. Geoid
has three wavelengths i.e. short, medium and long. From these three geoids, the long wavelength which
is obtained from the Global Geopotential Model (GGM) is the important one to determinant the geoid.
In 2008 Pavlis et al.  from National Geospatial-intellegence Agancy (NGA) had established the
global model - EGM2008 which has order and degree of 2190. This global model was validated and is
used to calculate the geoid undulation worldwide. To find better GGM Validation was carried out with
comparison between the geoid undulations from GGM with the geoid undulation from GPS-Leveling
observation data. The result of this validation shows that EGM2008 in Sumatera and EGM96 from
Lemoine et al.  in Java has better results compare with other GGM. The standard deviation of
the comparison of EGM2008 and GPS-Leveling is 33,4 cm which is the smallest in Sumatera and the
comparison of EGM96 and GPS-Leveling in Java with the value of 87,4 cm is the smallest but more
rougher than in Sumatera.
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