The complete spectral characterization of ultrashort pulses is demonstrated with a new diagnostic called Spectral Interferometry Resolved in Time Extra Dimensional. This method, based on spectral shearing interferometry, is self-referenced and self-calibrated. It yields directly to an interferogram pattern displaying an intuitive representation of the derivative of the spectral phase. No iterative algorithm is needed for phase measurement making this method suitable for real time and easy characterization. This technique is highlighted by the spectral phase characterization of pulses out of a folded nondispersive line and the pulse shape is compared with a trace recorded with an intensity autocorrelator.