Capacitive sensor for determining an instantaneous angular position (α R) of a rotatable element of a timepiece, the capacitive sensor comprising: - six stator electrodes (11, 12, 13, 21, 22, 23) formed as concentric arcs segments centered on the axis of rotation of the rotatable element, the first, third, fourth and sixth stator electrodes extending along 45°, and the second and fifth stator electrodes extending along 135°, the first and second, respectively the second and third, the fourth and fifth, and the fifth and sixth stator electrodes, extending along a common 45-degree angular portion, said four 45-degree angular portions being distinct, - one rotor electrode (5a, 5b) arranged to rotate with the rotatable element, the rotor electrode being made of two identical parts (5a, 5b) extending symmetrically on either side of its rotation axis along 90°, the rotor electrode (5a, 5b) and the stator electrodes (11, 12, 13, 21, 22, 23) being arranged to, during a rotation cycle of the rotatable element, provide capacitances (C 1, C 2, C 3, C 4) between two of the six stator electrodes (11, 12, 13, 21, 22, 23), such that each of the capacitances (C 1, C 2, C 3, C 4) varies over at least a portion of the said rotation cycle due to the influence of said rotor electrode (5a,5b), the capacitances (C 1, C 2, C 3, C 4) comprising a first differential capacitance pair comprising a first capacitance (C 1) formed between the first and second stator electrodes, and a second capacitance (C 2) formed between the second and third stator electrodes, the first capacitance (C 1) having an instantaneous first capacitance value X 1 and the second capacitance (C 2) having an instantaneous second capacitance value X 2 depending on the angular positioning of said rotor electrode (5a, 5b), the capacitances (C 1, C 2, C 3, C 4) comprising a second differential capacitance pair comprising a third capacitance (C 3) formed between the fourth and fifth stator electrodes, and a fourth capacitance (C 4) formed between the fifth and sixth stator electrodes, the third capacitance (C 3) having an instantaneous third capacitance value X 3 and the fourth capacitance (C 4) having an instantaneous fourth capacitance value X 4 depending on the angular positioning of said rotor electrode (5a, 5b), the capacitive sensor comprising a sensor driver circuit for sensing capacitance values X 1, X 2, X 3 and X 4, and for determining the instantaneous angular position (α R) by evaluating a first differential capacitance value X 1-2 = X 1 - X 2 and a second differential capacitance value X 3-4 = X 3 - X 4. - six stator electrodes (11, 12, 13, 21, 22, 23) formed as concentric arcs segments centered on the axis of rotation of the rotatable element, the first, third, fourth and sixth stator electrodes extending along 45°, and the second and fifth stator electrodes extending along 135°, the first and second, respectively the second and third, the fourth and fifth, and the fifth and sixth stator electrodes, extending along a common 45-degree angular portion, said four 45-degree angular portions being distinct, - one rotor electrode (5a, 5b) arranged to rotate with the rotatable element, the rotor electrode being made of two identical parts (5a, 5b) extending symmetrically on either side of its rotation axis along 90°,