1. A biometric method adapted for a biometric apparatus, comprising: the biometric apparatus providing an hashed registered data and an adjustment value, wherein the step of providing the hashed registered data and the adjustment value comprises: extracting a registered biometric data; defining a plurality of value ranges according to a threshold, wherein each of the value ranges has a quantization value; using the quantization value of one of the value ranges as a quantified registered data for replacing the registered biometric data if the registered biometric data falls within the value range; performing an one-way hash function to convert the quantified registered data into the hashed registered data; calculating a difference between the quantified registered data and the registered biometric data to obtain the adjustment value; and storing the adjustment value and the hashed registered data; the biometric apparatus extracting a biometric data; the biometric apparatus adjusting the biometric data to a adjusted biometric data according to the adjustment value; the biometric apparatus defining the value ranges according to the threshold, wherein each of the value ranges has a quantization value; the biometric apparatus using the quantization value of one of the value ranges as a quantified data for replacing the adjusted biometric data if the adjusted biometric data falls within the value range; the biometric apparatus performing the one-way hash function to convert the quantified data into an hashed data; and the biometric apparatus comparing the hashed registered data and the hashed data.