An organic light emitting display device comprising a display panel comprising: a plurality of data lines; a plurality of gate lines; a plurality of subpixels, wherein each subpixel is disposed where a data line and a gate line intersect, each subpixel having a circuit including a driving transistor; a sensing unit connected via a plurality of sensing lines to the circuits, the sensing unit configured to sense a voltage of a drain or source electrode of each of the driving transistors, a gate driving unit configured to sequentially output a gate signal to the gate lines; a data driving unit configured to drive the data lines to provide: a data voltage (DATA) to the data lines according to the gate signal during a display frame (n-TH FRAME), and a data voltage waveform to the data lines during an interframe time before the display frame, wherein the interframe time includes the following sequence of periods: a sensing period, a black period, a recovery period, and a pre-data period before the display frame; and a timing controller configured to control the gate driving unit and the data driving unit, and, using the voltage sensed by the sensing unit, perform a real-time pixel compensation which changes the data voltage (DATA) provided to each subpixel, wherein the data voltage waveform provided by the data driving unit to the data lines during the interframe time before the display frame comprises: (i) during the sensing period, applying data voltages (DATA+VTH), which are compensated for the threshold voltage of the driving transistor in each subpixel sensed when a power off signal of the organic light emitting display device is generated, as sensing signals to detect the mobility of the driving transistor, (ii) during the black period, black data, (iii) during the recovery period, recovery data corresponding to black data or white data for resetting the driving transistor in each subpixel, and (iv) during the pre-data period, data voltages (Pre) identical to the data voltages of a first gate line and/or a second gate line of the display frame during the display frame, wherein the recovery data swings over a plurality of consecutive frames in an irregular pattern between black and white data. a plurality of data lines; a plurality of gate lines; a plurality of subpixels, wherein each subpixel is disposed where a data line and a gate line intersect, each subpixel having a circuit including a driving transistor; a sensing unit connected via a plurality of sensing lines to the circuits, the sensing unit configured to sense a voltage of a drain or source electrode of each of the driving transistors, a gate driving unit configured to sequentially output a gate signal to the gate lines; a data driving unit configured to drive the data lines to provide: a data voltage (DATA) to the data lines according to the gate signal during a display frame (n-TH FRAME), and a data voltage waveform to the data lines during an interframe time before the display frame, wherein the interframe time includes the following sequence of periods: a sensing period, a black period, a recovery period, and a pre-data period before the display frame; and a data voltage (DATA) to the data lines according to the gate signal during a display frame (n-TH FRAME), and a data voltage waveform to the data lines during an interframe time before the display frame, wherein the interframe time includes the following sequence of periods: a sensing period, a black period, a recovery period, and a pre-data period before the display frame; and a timing controller configured to control the gate driving unit and the data driving unit, and, using the voltage sensed by the sensing unit, perform a real-time pixel compensation which changes the data voltage (DATA) provided to each subpixel, wherein the data voltage waveform provided by the data driving unit to the data lines during the interframe time before the display frame comprises: (i) during the sensing period, applying data voltages (DATA+VTH), which are compensated for the threshold voltage of the driving transistor in each subpixel sensed when a power off signal of the organic light emitting display device is generated, as sensing signals to detect the mobility of the driving transistor, (ii) during the black period, black data, (iii) during the recovery period, recovery data corresponding to black data or white data for resetting the driving transistor in each subpixel, and (iv) during the pre-data period, data voltages (Pre) identical to the data voltages of a first gate line and/or a second gate line of the display frame during the display frame, (i) during the sensing period, applying data voltages (DATA+VTH), which are compensated for the threshold voltage of the driving transistor in each subpixel sensed when a power off signal of the organic light emitting display device is generated, as sensing signals to detect the mobility of the driving transistor, (ii) during the black period, black data, (iii) during the recovery period, recovery data corresponding to black data or white data for resetting the driving transistor in each subpixel, and (iv) during the pre-data period, data voltages (Pre) identical to the data voltages of a first gate line and/or a second gate line of the display frame during the display frame, wherein the recovery data swings over a plurality of consecutive frames in an irregular pattern between black and white data.