A seat belt retractor is provided for a motor vehicle with a receiving part for a seat belt retractable on the receiving part, a deceleration sensor for detecting a deceleration in the seat belt retractor, a first extension speed sensor for detecting an extension speed of the seat belt prior to activating an energy absorption device. The energy absorption device fixes the seat belt during an accident with energy absorption, so that when a first deceleration limit detected by the deceleration sensor is exceeded the seat belt is restrained with energy absorption. The seat belt retractor encompasses a locking mechanism for securing the seat belt and a second extension speed sensor for detecting an extension speed after activating the energy absorption device. When a second extension speed limit of the seat belt has been exceeded, the locking mechanism restrains the seat belt without energy absorption.