In an embodiment, the present invention provides a device for measuring the pressure p of a fluid flowing through a pipeline, including: at least one primary sensor arranged on an outer periphery of the pipeline for measuring a primary physical measured variable which is dependent on the pressure p, the absolute value of the pressure p being obtainable by offsetting said primary physical measured variable against at least one calibration datum, the at least one calibration datum relating to the geometry and/or to at least one material property of the pipeline; and a calibration datum determining unit and an evaluation unit for determining the pressure p from the primary physical measured variable in conjunction with the calibration datum. The calibration datum determining unit includes a measuring pipe which can be fluidically connected to the pipeline, which differs from the rest of the pipeline in material and/or in cross-sectional geometry.