File carving is a technique to extract data from digital evidence and the signature-based approach searches data for patterns of file signature. As a response to demands of employing a high-performance string searching algorithm, the baseline algorithm, namely Boyer-Moore algorithm, is being widely used since proposed. However, there are more algorithms which are better than it, being continually proposed. Therefore, this paper aims to identify the best string searching algorithm that can be used for optimizing the signature-based file carving in term of time and memory usage. Therefore, a performance analysis against the baseline algorithm and its variations are performed. The findings indicate that the Shift-Or (SO) algorithm can be used as string searching algorithm in signature-based file carving due to its faster completion time and lower memory consumption. For future work, SO algorithm will be integrated with the file carving tools to test the capability of reducing the carving duration and memory usage while maintaining the similar carving accuracy.