API Overview | FormantAI

The FormantAI Voice API lets your backend initiate calls, launch batch campaigns, retrieve conversations, download recordings, submit transcription jobs, render podcasts, and voice text to speech.

Base URL

https://api.voice.formantai.com

Regional environments:

Region	Base URL
Global	`https://api.voice.formantai.com`
India	`https://api.in.voice.formantai.com`

Authentication

Use an API key as a bearer token.

Authorization: Bearer YOUR_API_KEY

Resources

Resource	Description
Calls	Start one outbound call immediately or schedule one for later.
Batch Calls	Upload CSV campaigns and inspect campaign metrics.
Conversations	Retrieve call history, transcripts, results, trace IDs, and recordings.
Transcription	Submit audio files for asynchronous transcription.
Podcast	Render source material into a multi-speaker audio episode.
Text to Speech	Voice a batch of texts with ElevenLabs, Sarvam, Smallest or Vakyam and download one clip per text.
Webhooks	Receive real-time terminal call events without polling.

Request formats

JSON endpoints require Content-Type: application/json.
File upload endpoints use multipart/form-data.
List endpoints use limit and offset pagination.

Recommended integration order

Create an API key in the dashboard.
Select or create an agent.
Make one test call with POST /v1/call.
Configure a webhook target on the agent.
Fetch the completed conversation to confirm transcript, results, and recording.
Add batch calls if your workflow needs campaigns.

Important IDs

ID	Where it comes from	Where it is used
`agent_id`	Dashboard agent page	Calls, batch calls, conversation filters, webhook payloads
`conversation_id`	Conversation record or webhook payload	Fetch details and recordings
`trace_id`	`POST /v1/call` response	Debugging and support
`batch_id`	`POST /v1/batch-call` response	Fetch batch detail and metrics
`event_id`	Webhook delivery	Dedupe webhook processing

Next steps

Make a Call

Start with the most important endpoint.

Webhooks

Receive real-time call outcomes.