List of free data-visualizations stuff for developerππ½
If you're looking for all programming tools around data-visualizations (not just free). Check this page List of data-visualizations Programming Tools

Google Colab
Colab is a free Jupyter notebook environment that runs entirely in the cloud.
Tag: data-science, data-visualizations

Kaggle
Kaggle is the world's largest data science community with powerful tools and resources to help you achieve your data science goals.
Tag: data-science, data-visualizations

Jupyter Notebook
Jupyter Notebook is an open-source web application that allows you to create and share documents that contain live code, equations, visualizations and narrative text.
Tag: data-science, data-visualizations
Open Source