System (100; 200; 300; 400; 500) for detecting a measurement current (J m), having: - a shunt resistor, wherein the shunt resistor has • two measurement terminals (2a; 2b) for applying a measurement current (J m), wherein the measurement current flows through the shunt resistor along a main current direction; • slot structures (7; 8), which divide the shunt resistor along the main current direction into two side current regions (5; 6) each having a first width (W1; W2) and a main current region having a second width, wherein the side current regions (5; 6) and the main current region are made of the same material; and • two calibration terminals (5c; 6c), which are connected to the side current regions (5; 6) transversely to the main current direction, wherein the calibration terminals (5c, 6c) are each connected halfway up the side current regions (5, 6), and - a detection circuit, which is connected to the measurement terminals (2a; 2b) of the shunt resistor and which is configured to detect a measurement current (J m) flowing through the shunt resistor and to generate a measurement signal depending on the detected measurement current (J m); characterized in that the second width of the shunt resistor is larger than the first width (W1; W2); and in that the system further comprises - a calibration device, which is connected to the calibration terminals (5c; 6c) and which is configured to apply a reference voltage or a reference current to the two calibration terminals (5c; 6c) and to determine a calibration voltage depending on a voltage dropped across the two calibration terminals (5c; 6c); and - a correction circuit (20; 26), which is connected to the calibration device and the detection circuit and which is configured to correct the measurement signal generated by the detection circuit depending on the detected calibration voltage. - a shunt resistor, wherein the shunt resistor has • two measurement terminals (2a; 2b) for applying a measurement current (J m), wherein the measurement current flows through the shunt resistor along a main current direction; • slot structures (7; 8), which divide the shunt resistor along the main current direction into two side current regions (5; 6) each having a first width (W1; W2) and a main current region having a second width, wherein the side current regions (5; 6) and the main current region are made of the same material; and • two calibration terminals (5c; 6c), which are connected to the side current regions (5; 6) transversely to the main current direction, wherein the calibration terminals (5c, 6c) are each connected halfway up the side current regions (5, 6), and • two measurement terminals (2a; 2b) for applying a measurement current (J m), wherein the measurement current flows through the shunt resistor along a main current direction; • slot structures (7; 8), which divide the shunt resistor along the main current direction into two side current regions (5; 6) each having a first width (W1; W2) and a main current region having a second width, wherein the side current regions (5; 6) and the main current region are made of the same material; and • two calibration terminals (5c; 6c), which are connected to the side current regions (5; 6) transversely to the main current direction, wherein the calibration terminals (5c, 6c) are each connected halfway up the side current regions (5, 6), - a detection circuit, which is connected to the measurement terminals (2a; 2b) of the shunt resistor and which is configured to detect a measurement current (J m) flowing through the shunt resistor and to generate a measurement signal depending on the detected measurement current (J m); - a calibration device, which is connected to the calibration terminals (5c; 6c) and which is configured to apply a reference voltage or a reference current to the two calibration terminals (5c; 6c) and to determine a calibration voltage depending on a voltage dropped across the two calibration terminals (5c; 6c); and - a correction circuit (20; 26), which is connected to the calibration device and the detection circuit and which is configured to correct the measurement signal generated by the detection circuit depending on the detected calibration voltage.