Numcodecs is a Python package providing buffer compression and transformation codecs for use in data storage and communication applications. These include: Compression codecs, e.g., Zlib, BZ2, LZMA, ZFPY and Blosc. Pre-compression filters, e.g., Delta, Quantize, FixedScaleOffset, PackBits, Categorize. Integrity checks, e.g., CRC32, Adler32. All codecs implement the same API, allowing codecs to be organized into pipelines in a variety of ways.