python-blosc comes with C Blosc sources, so it does not depend on any other library (bar Python itself of course). Of course, if you are going to install from sources, you are going to need a C compiler (GCC, clang and MSVC 2008/2010/2012/2015 have been tested).

Also, there are situations where you may want to link with an already existing Blosc library in your system. You can do that too.

This package supports Python 2.6, 2.7 and 3.3 or higher versions.

Installing from PyPI repository


$ pip install -U blosc

Building manually

First, go to the python-blosc official repository at and download the sources.

Then, there are different ways to compile python-blosc, depending on whether you want to link with an already installed Blosc library or not.

Compiling without an installed Blosc library

python-blosc comes with the Blosc sources with it so, assuming that you have a C compiler installed, do:

$ python build_ext --inplace

That’s all. You can proceed with testing section now.

Compiling with an installed Blosc library

In case you have Blosc installed as an external library (and disregard the included Blosc sources) you can link with it in a couple of ways.

Using an environment variable:

$ BLOSC_DIR=/usr/local     (or "set BLOSC_DIR=\blosc" on Win)
$ export BLOSC_DIR         (not needed on Win)
$ python build_ext --inplace

Using a flag:

$ python build_ext --inplace --blosc=/usr/local

Generating Sphinx documentation

In case you want to generate the documentation locally, you will need to have the Sphinx documentation system, as well as the numpydoc extension, installed. Then go down to doc/ directory and do:

$ make html|latex|latexpdf


After compiling, you can quickly check that the package is sane by running the doctests in blosc/

$ PYTHONPATH=.   (or "set PYTHONPATH=." on Win)
$ export PYTHONPATH=.  (not needed on Win)
$ python blosc/  (add -v for verbose mode)

Or alternatively, you can use the third-party nosetests script to run both the doctests and the test suite:

$ nosetests --with-doctest (add -v for verbose mode)

Once installed, you can re-run the tests at any time with:

$ python -c "import blosc; blosc.test()"


Install it as a typical Python package:

$ python install