Converting latitude and longitude to/from Israel Transverse Mercator (ITM) coordinates

קראו עמוד זה בעברית

The standard coordinate grid in Israel is called Israel Transverse Mercator (ITM), and is sometimes informally referred to as the "new Israel grid" (רשת ישראל חדשה). This grid appears in detailed maps of Israel. Nonetheless, the older and less accurate Israel Cassini Soldner (ICS) grid or "old Israel grid" (רשת ישראל ישנה) is also still used in many places. For example, despite the official adoption of ITM in 1994, the ICS grid is still displayed more prominently in Israeli hiking maps (מפות סימון שבילים) and is consequently more commonly used by hikers.

The ITM grid is a transverse Mercator projection, meaning that the surface of the earth is projected onto a cylinder whose axis of symmetry is parallel to the equator. This provides an accurate projection along a longitudinal slice of the earth, with the inaccuracy increasing as one moves away from this axis. Thus, for example, the Universal Transverse Mercator (UTM) grid divides the earth into 60 longitudinal slices, each projected separately. Since Israel is a narrow country, whose span from east to west barely exceeds 100 kilometers, a single projection is sufficient for accurately representing the entire area.

Conversion from lat-long to ITM

Latitude: ° North
Longitude: ° East
ITM: -
Old Grid: -

Conversion from ITM to lat-long

ITM East: meters
ITM North: meters
Latitude: ° North
Longitude: ° East

Some notes on the ICS grid

Acknowledgements

The code in this page is based on the Proj4.js library whose source code is available here. Proj4.js is distributed under this license.

Alternative ITM conversion programs

Several people have written versions of ITM-to-WGS84 conversion code in other languages, and have graciously allowed me to host their code on my site. These are:

Back to Zvika's software page