VOICE API

Voice that scales like software, on a network we own.

Build call tracking, AI Voice Agents, number masking, IVR, and conversation intelligence on a single API. Backed by carrier-grade SLAs in 220+ countries — because we are the carrier in those countries.

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82%

Gross margin on Voice API workloads. The economics of owned infrastructure.

220+

Countries covered with our own carrier interconnects.

10+ yrs

Average tenure of our top 5 Voice API marketplace customers.

We own the carrier layer.

Twilio, Vonage, Plivo, and Sinch resell capacity from carriers like us. CALLR is the carrier — registered in France, with direct fiber interconnects and our own E.164 number ranges. That changes what we can promise on latency, on routing, on cost, and on what stays in Europe.

Built API-first, for marketplaces.

Number masking for buyer-seller privacy. Per-listing call attribution for advertiser ROI. Real-time webhooks into your CRM. Built into the API from day one because that’s what marketplaces actually need — not bolted on as a generic CPaaS feature.

AI on top of carrier-grade rails.

Voice AI is only as reliable as the network underneath. Connect OpenAI Realtime, ElevenLabs, or Vapi over SIP — or use our own Voice Agents. Either way, the call lands on infrastructure we control end-to-end.

Number masking

Connect buyer and seller without exposing real numbers. Privacy by design.

Call tracking

Per-listing, per-advertiser, per-campaign attribution. Prove ROI to your buyers.

AI Voice Agents

Deploy a fully-functioning agent in one line of YAML. Bring your model or use ours.

IVR & call routing

Visual flow builder, full programmability via REST API and Callr Actions.

Recording & transcription

Real-time and batch. EU-resident. Searchable.

Conversation intelligence

Intent, sentiment, qualification, structured lead extraction. On every call.

Number provisioning

Mobile and landline. 220+ countries. From a single API.

CRM & webhooks

Salesforce, HubSpot, custom. Every call event in real time.

Built into the largest marketplaces in Europe.

BUILT API-FIRST

Deploy an AI Voice Agent in one line of YAML.

Same Voice API. Native SIP connections to OpenAI Realtime, ElevenLabs, and Vapi. MCP server included — Claude, Cursor, and other AI tools can manage your call flows directly.

voicebot.yaml

Run the voice layer of your marketplace on infrastructure you can trust.

30-day attribution audit. We instrument 10 listings. You see what every inbound call is worth. No commitment.

Start the auditTalk to engineering