A system and method are provided for parallel processing data that is forward error correction (FEC) protected with multiple codewords. The method accepts an electrical waveform representing a digital wrapper frame of interleaved FEC codewords. Typically, the codeword encoding is solved using an algorithm such as linear block codes, cyclical block codes, Hamming, Reed-Solomon, or Bose-Chaudhuri-Hocquenghem (BCH). The method calculates a first set of syndromes for a first codeword. In parallel with the calculation of the first set of syndromes, a second set of syndromes is calculated for a second codeword with a data component shared with the first codeword. Using the first set of syndromes, an error magnitude and location (EML) of the first codeword is performed. Using the second set of syndromes, an EML of the second codeword is performed in parallel with the EML of the first codeword.