An information processing apparatus, comprising: an acquisition module (131, 132, 133, 134) configured to acquire a basic first attribute of a user, a second attribute related to a physique of the user, a third attribute, and a biological signal related to a living body of the user, a feature calculator configured to calculate a feature in the biological signal and a blood pressure value calculator configured to calculate a blood pressure value of the user, based on the first attribute, the second attribute, the third attribute, and the feature, the information processing apparatus further comprising: an acceleration measurement module configured to measure an acceleration signal related to acceleration, and an estimator configured to estimate an attitudinal state of the user, based on the acceleration signal, wherein the first attribute includes at least one of age, sex and race of the user, the second attribute includes at least one of a regional length of a body region of the user and an index value indicating a degree of a corpulent physique of the user, the biological signal includes a first pulse wave signal related to a pulse wave at a first body surface position of the user, and a second pulse signal related to a pulse wave at a second body surface position of the user different from the first body surface position, or a pulse wave signal related to a pulse wave or an electrocardiographic signal related to an electrical activity of a heart of the user, and the feature includes at least one of a pulse wave transit time and a pulse wave velocity based on the first pulse wave signal and the second pulse wave signal or the electrocardiographic signal, and/or at least one of a heartbeat interval and heart rate calculated based on the pulse wave signal or the electrocardiographic signal, characterized in that the third attribute is related to a circulatory organ of the user, the third attribute including a blood test result of the user, the blood pressure value calculator is configured to calculate the blood pressure value using a parameter according to the attitudinal state. an acquisition module (131, 132, 133, 134) configured to acquire a basic first attribute of a user, a second attribute related to a physique of the user, a third attribute, and a biological signal related to a living body of the user, a feature calculator configured to calculate a feature in the biological signal and a blood pressure value calculator configured to calculate a blood pressure value of the user, based on the first attribute, the second attribute, the third attribute, and the feature, the information processing apparatus further comprising: an acceleration measurement module configured to measure an acceleration signal related to acceleration, and an estimator configured to estimate an attitudinal state of the user, based on the acceleration signal, wherein an acceleration measurement module configured to measure an acceleration signal related to acceleration, and an estimator configured to estimate an attitudinal state of the user, based on the acceleration signal, wherein the first attribute includes at least one of age, sex and race of the user, the second attribute includes at least one of a regional length of a body region of the user and an index value indicating a degree of a corpulent physique of the user, the biological signal includes a first pulse wave signal related to a pulse wave at a first body surface position of the user, and a second pulse signal related to a pulse wave at a second body surface position of the user different from the first body surface position, or a pulse wave signal related to a pulse wave or an electrocardiographic signal related to an electrical activity of a heart of the user, and the feature includes at least one of a pulse wave transit time and a pulse wave velocity based on the first pulse wave signal and the second pulse wave signal or the electrocardiographic signal, and/or at least one of a heartbeat interval and heart rate calculated based on the pulse wave signal or the electrocardiographic signal, characterized in that the third attribute is related to a circulatory organ of the user, the third attribute including a blood test result of the user, the blood pressure value calculator is configured to calculate the blood pressure value using a parameter according to the attitudinal state.