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Model Card Toolkit Concepts

Model Card

Model Cards are machine learning documents that provide context and transparency into a model's development and performance. They can be used to share model metadata and metrics with researchers, developers, reporters, and more.

Some use cases of model cards include:

  • Facilitating the exchange of information between model builders and product developers.
  • Informing users of ML models to make better-informed decisions about how to use them (or how not to use them).
  • Providing model information required for effective public oversight and accountability.


The Model Card schema is a JSON schema describing a model card's available fields. These JSON objects can be interfaced with other systems for storage, analysis, or visualization.


The graphic.image field is encoded as a base64-encoded string. The Model Card Toolkit can help with generating base64 images - see Model Card API.

Model Card Toolkit

The Model Card Toolkit allows you to generate Model Card documents and JSON objects with a streamlined Python interface.

Model Card API

The Model Card Toolkit includes a Model Card API consisting of a Python class. Updates made to a Model Card Python object are written to a Model Card JSON object.


The function can be used to convert Matplotlib figures to base64 strings.

Model Card Documents

By default, the generated model card document is a HTML file based on default_template.html.jinja. However, you can provide your own template file to generate model cards in ModelCardToolkit.export_format(). These template files can be any text-based format (HTML, Markdown, LaTeX, etc.).

TFX and MLMD Integration

The Model Card Toolkit integrates with the TensorFlow Extended and ML Metadata tools. A Metadata Store can be used during Model Card Toolkit initialization to pre-populate many model card fields and generate training and evaluation plots. See this demonstration for a detailed example.