The invention relates to a system for determining the height of a tripod-mounted geodetic tool using a reference area. Said system comprises a spacer element (20) to be mounted on the tripod (25) and means (2) for linear measurement which are to be applied on the spacer element (20). A scale is disposed on the means (2) in such a manner as to directly indicate the height (h) of the tool (28). The means are preferably configured as a tape measure (2) or a plumb bar (1′). The invention provides a means for measuring the height of the tool outside the plumb line (32) with a sufficient amount of exactness and without substantial additional costs and/or effort.