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Get your API Key

SignatureAPI actions and triggers in Power Automate authenticate using an API key. If you haven’t already, sign up for a free SignatureAPI account. To get your API key:
  1. Go to Dashboard > Settings > API Key.
  2. Click to copy your test API key.

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Test vs Live Mode

Test API keys let you create envelopes for testing your flows. These envelopes:
  • Don’t send real emails to recipients (but you can preview them in the Email section of your dashboard).
  • Are not legally binding.
  • Are free to use.
When you’re ready to send real, legally-binding envelopes, add a payment method and get a live API key. Envelopes created in live mode:
  • Send actual emails to recipients.
  • Are legally binding.
  • Are billed.

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Creating a Connection

The first time you add a SignatureAPI trigger or action in Power Automate, you’ll be asked to create a connection.
You can name the connection—for example, SignatureAPI Test or SignatureAPI Live, depending on which API key you’re using.