Embodiments of ECC encoders supporting multiple code rates and throughput speeds for data storage systems are disclosed. In one embodiment, an encoder can provide for flexible and scalable encoding, particularly when quasi-cyclic low-density parity-check code (QC-LDPC) encoding is used. The encoder can be scaled in size based on, for example, the desired encoding throughput and/or computational cycle duration. The encoder can thus be used to support multiple code rates and throughput speeds. Accordingly, encoding speed and efficiency and system performance is improved.