b-tagging calibration using $t\bar{t}$events with the ATLAS experiment

Results of b-tagging calibration measured in 35 pb^{−1} of data collected by the ATLAS detector from the Large Hadron Collider pp collisions at sqrt{s} = 7 TeV in 2010 are presented. Two different approaches, using jets containing muons and jets originating from top quark pair event candidates are discussed. The measurement on the dijet sample was performed using the pTrel and system8 methods, while in the top quark pairs sample a kinematic selection and a tag counting methods were used. The results are provided in the form of data-to-simulation scale factors.