'Library not loaded: @rpath/libcudart.7.5.dylib' TensorFlow Error on Mac

This error message is displayed if you install the GPU-enabled Mac OS version of TensorFlow (available from release 0.10 onwards) on a machine that does not have CUDA installed.

To fix the error, install the CPU version for Python 2.7 or 3.x, as follows:

# Mac OS X, CPU only, Python 2.7:
$ export TF_BINARY_URL=https://storage.googleapis.com/tensorflow/mac/cpu/tensorflow-0.12.0-py2-none-any.whl
$ sudo pip install --upgrade $TF_BINARY_URL

# Mac OS X, CPU only, Python 3.4 or 3.5:
$ export TF_BINARY_URL=https://storage.googleapis.com/tensorflow/mac/cpu/tensorflow-0.12.0-py3-none-any.whl
$ sudo pip3 install --upgrade $TF_BINARY_URL

See tensorflow versions: https://www.tensorflow.org/versions/

To add to @mrry's answer, if you already have CUDA installed but you still get the error, it could be because the CUDA libraries are not on your path. Add the following to your ~/.bashrc or ~/.zshrc:

# export CUDA_HOME=/Developer/NVIDIA/CUDA-7.5 ## This is the default location on macOS
export CUDA_HOME=/usr/local/cuda
export DYLD_LIBRARY_PATH="$CUDA_HOME/lib:$DYLD_LIBRARY_PATH"
export PATH="$CUDA_HOME/bin:$PATH"

Uncomment either of the CUDA_HOMEs or edit it so that it contains your CUDA install. If you do not know where it is installed, try:

find / -name "*libcudart*"