A magnetic sensor comprising: a bridge circuit having a first magnetic sensor element and a second magnetic sensor element, each of the first magnetic sensor element and the second magnetic sensor element having a fixed magnetic layer, a nonmagnetic intermediate layer, and a free magnetic layer, the fixed magnetic layer having a first ferromagnetic layer, a second ferromagnetic layer, and an antiparallel coupling layer which is located between the first ferromagnetic layer and the second ferromagnetic layer, the first ferromagnetic layer and the second ferromagnetic layer being antiferromagnetically coupled together through the antiparallel coupling layer, and a magnetization direction of the fixed magnetic layer in the first magnetic sensor element and a magnetization direction of the fixed magnetic layer in the second magnetic sensor element being different from each other, wherein in a case where magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the first magnetic sensor element are respectively set to be Mst11 and Mst12 and magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the second magnetic sensor element are respectively set to be Mst21 and Mst22, in a case of Mst11>Mst12, a relationship of Mst21>Mst22 is satisfied, and in a case of Mst11<Mst12, a relationship of Mst21<Mst22 is satisfied, characterised in that magnetization amount is adjusted by changing a thickness or saturation magnetization and a magnitude relationship between the magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer is determined by measuring a magnetic field-resistance curve of the magnetic sensor element for evaluating a balance between the first ferromagnetic layer and the second ferromagnetic layer. a bridge circuit having a first magnetic sensor element and a second magnetic sensor element, each of the first magnetic sensor element and the second magnetic sensor element having a fixed magnetic layer, a nonmagnetic intermediate layer, and a free magnetic layer, the fixed magnetic layer having a first ferromagnetic layer, a second ferromagnetic layer, and an antiparallel coupling layer which is located between the first ferromagnetic layer and the second ferromagnetic layer, the first ferromagnetic layer and the second ferromagnetic layer being antiferromagnetically coupled together through the antiparallel coupling layer, and a magnetization direction of the fixed magnetic layer in the first magnetic sensor element and a magnetization direction of the fixed magnetic layer in the second magnetic sensor element being different from each other, wherein in a case where magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the first magnetic sensor element are respectively set to be Mst11 and Mst12 and magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the second magnetic sensor element are respectively set to be Mst21 and Mst22, in a case of Mst11>Mst12, a relationship of Mst21>Mst22 is satisfied, and in a case of Mst11<Mst12, a relationship of Mst21<Mst22 is satisfied, characterised in that magnetization amount is adjusted by changing a thickness or saturation magnetization and a magnitude relationship between the magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer is determined by measuring a magnetic field-resistance curve of the magnetic sensor element for evaluating a balance between the first ferromagnetic layer and the second ferromagnetic layer.