Learn how to quickly and easily embed Carta data into your app.

Discover APIs, integration guides and other documentation to embed Carta data into your systems and workflows.

Carta’s developer platform is part of our mission to empower partner organizations to provide a better service to our joint customers through connected and accurate data. Our APIs are built to enable robust integrations to better serve our network of equity owners, stakeholders, investors and partners and support your team’s unique use cases.

Explore our APIs


Allows incorporation partners and law firms to programmatically send new customers to Carta

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Allows fund operators to retrieve summary cap table insights for their portfolio holdings

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Allows law firms and technology partners to fetch cap table information on behalf of the company

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Allows personal finance management partners to aggregate holdings inclusive of equity data

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Apply to become a beta partner

For early access to our developer tools, we ask interested partners to fill out this form and reach out to [email protected]. Our team reviews responses monthly and we’ll reach out when we can further explore an integration with you. We'll discuss your business needs, how we can help you work with our data, and confirm technical needs.

Requirements for beta partners include:

  • Your organization is a Carta customer
  • You have a clear use case that can be solved using our existing API endpoint (noted below)
  • You have resources to develop the integration within the next 3-6 months

Try our mocking service

We invite you to experiment with our mocking service while waiting for our team to process your application. It doesn't require genuine credentials and always returns static but valid responses to your requests. Go to our API Reference, select the option for the Base URL, and specify any string for OAuth2 authentication. Click Try It! and you will see an example response to that request.

Start building

Got your invite code? Great! Let’s get started. Here’s how a typical integration looks like:


  • Follow our quickstart guide to register for Carta’s developer portal and create your Playgrounds app
  • Schedule a progress check-in call with Carta
  • Share an estimate for your target launch timeframe



  • Once your production access request is approved, we’ll share your production API keys
  • Do internal validation to confirm data is flowing as expected
  • Share support and enablement resources with your teams and/or customers as needed
  • Take your integration live
  • Track customer feedback and schedule a check-in call with our team for 2 months out