AI Voice Agents
Natural, interruptible conversations with streaming speech recognition and low-latency synthesis. Your agents listen, reason and respond like your best rep.
Realtime voice infrastructure, self-hosted
AI voice agents that answer every call
Design conversational agents on a visual canvas, then put them everywhere your customers are — web, mobile, SIP trunks and phone numbers — on realtime infrastructure you control.
Self-hosted
Multi-tenant by design
Sub-second realtime
Sub-second
Voice-to-voice latency, tuned across the whole media path.
99.9%
Uptime target on infrastructure we run and monitor ourselves.
Unlimited
Concurrent sessions by architecture — capacity scales horizontally.
Per-tenant
A dedicated database for every workspace. Hard isolation, not row filters.
Product
Everything a voice agent needs, in one platform
From the first “hello” to the analytics after hang-up — Vollo covers the full lifecycle of a production voice agent.
Smart Call Routing
Route by intent, language, business hours or caller history. Escalate to a human with full context the moment a conversation needs one.
Real-time Insights
Live transcripts, sentiment, intent and outcome analytics for every session. Watch calls as they happen and replay them after.
Visual Workflow Builder
Drag, drop and connect nodes on a canvas — triggers, prompts, branches, tools and hand-offs. Ship changes without touching code.
Telephony & SIP
Connect Twilio or any SIP trunk, provision numbers, and take the same agent to landlines, mobiles and browser calls alike.
Enterprise Ready
Multi-tenant isolation with a dedicated database per workspace, role-based access, audit trails and SSO-ready authentication.
How it works
From canvas to live calls in an afternoon
No fine-tuning pipelines, no telephony PhD. Three steps stand between you and an agent on the line.
Design visually
Compose your agent on a drag-and-drop canvas — greetings, intents, branches, tool calls and hand-off rules, all versioned.
Connect your number
Link a Twilio account or point any SIP trunk at Vollo. Provision new numbers or bring the ones your customers already know.
Go live everywhere
One click deploys the same agent to phone lines, your website and your mobile app — with analytics from the first second.
Telephony
Bring your own carrier — or your whole PBX
Vollo speaks SIP natively. Keep your numbers, keep your carrier contracts, and put an AI agent in front of any of them.
- Twilio in minutes — paste credentials, pick a number, route it to an agent.
- Any SIP trunk — registration or IP-auth trunks from any provider terminate directly on Vollo.
- Elastic numbers — provision, port and reassign numbers per project and per tenant.
- Web & mobile calls — the same agent answers browser and in-app calls through the SDK.
+1 (415) 555-0132
→ reception-agent
Live
+44 20 7946 0958
→ support-triage
Live
sip:desk@pbx.acme.co
→ after-hours
SIP
widget · acme.com
→ sales-qualifier
Web
Developers
An API you’ll actually enjoy
Everything in the dashboard is a REST call away. Start a call, stream events, meter usage — programmatically, per tenant.
- REST API for agents, calls, numbers and workflows — predictable, versioned, JSON.
- Scoped API keys per project and environment, rotatable without downtime.
- Webhooks for the full call lifecycle — ringing, answered, transcript, completed.
- Usage metering built in — voice minutes tracked per tenant, exportable for billing.
# Place an outbound call from your agent
curl -X POST https://api.vollo.io/api/v1/calls \
-H "Authorization: Bearer $VOLLO_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"agent_id": "agt_9f2c1b8d",
"to": "+14155550132",
"from": "+14155550199",
"metadata": { "crm_id": "cus_84h2" },
"webhook_url": "https://example.com/hooks/vollo"
}'
# 201 Created
{ "id": "call_hv82k1", "status": "ringing" }
Pricing
Start free, scale when your callers do
Every plan meters simple, honest voice minutes — one minute of live conversation is one minute, on any channel.
Free
For prototypes and weekend builds. No card required.
$0/month
Start for free
- 100 voice minutes per month
- 1 project
- 2 team members
- Visual workflow builder
- Web calls & test numbers
- Community support
Pro
For teams putting an agent in front of real customers.
$49/month
Start with Pro
- 1,000 voice minutes per month
- Unlimited workflows
- 5 phone numbers
- Twilio & SIP trunking
- Webhooks & full REST API
- Email support
Business
For companies where the phone line is the front door.
$199/month
Talk to us
- 5,000 voice minutes per month
- Everything in Pro
- SSO-ready authentication
- Dedicated database per tenant
- Priority support
- Uptime & latency reporting
Voice minutes are metered per second and pooled across your projects. Need more? Additional minutes and custom plans are available in the dashboard.
FAQ
Questions, answered
Is Vollo really self-hosted?
Yes — the realtime media plane runs on infrastructure we operate ourselves rather than a third-party CPaaS, which is how we keep latency low and costs predictable. Enterprise customers can also deploy the full stack into their own environment; the docs cover both models.
Which telephony providers can I use?
Twilio works out of the box with a guided setup. Beyond that, any provider that offers SIP trunking — registration-based or IP-authenticated — can terminate calls on Vollo, so you can keep existing carriers, contracts and numbers.
Can I bring my own model and voice keys (BYOK)?
Yes. You can plug in your own API keys for LLM, speech-to-text and text-to-speech providers, so usage is billed on your own accounts and you choose exactly which models your agents run on. Platform-managed keys are available if you'd rather not think about it.
How is my data isolated from other customers?
Every tenant gets a dedicated database — not shared tables with row-level filters. Transcripts, recordings, workflows and API keys live in your own database instance, which makes isolation auditable and per-tenant export or deletion straightforward.
How does the realtime layer work?
Vollo Realtime is our own WebRTC media plane, which we host and tune for voice. It handles media transport for web, mobile and SIP sessions, giving every channel the same sub-second conversational loop.
Is there a trial? Do I need a credit card?
The Free plan is a permanent trial: 100 voice minutes every month, one project and two team members, with no credit card required. Upgrade to Pro or Business whenever you're ready — your workflows and numbers come with you.
Your next call could answer itself
Build a voice agent on the canvas today. Put it on a real phone number before your coffee goes cold.