Kallflow LogoKallflow
New: On-Premise Voice Engine 2.0

The free, self-hosted
to build, monitor and sell voice agents

Deploy on your own server in minutes. Keep your data, your agents, and your margins. Zero platform fees, forever.

TRUSTED BY GROWING TEAMS
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Explore a real hosted installation directly from the landing page.

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Why Self-Host

We provide the tools, you hold the keys. Full control, security, and performance that cloud APIs can't match.

No Vendor Lock-in

Your data and configuration are yours. Export whenever you want. Agent code is also exportable; some parts may require adjustments outside Kallflow.

Local Models Coming Soon

AI & Model Control

Choose providers or use local models. Audio stays in your infra if you want.

Predictable Costs

No per-minute surprises. Cost scales with your infrastructure, not usage.

Controlled Latency

Deploy close to your users. No hops to external APIs.

Zero External Uptime Dependency

Your SLA is your SLA. You don't depend on third parties to operate.

Deployment Customization

Adapt network, security, scaling, and redundancy to your needs.

No vendor lock-in. Latency tuned for real-time voice. Designed for compliance-focused environments.

Built for Every Scale

Whether you're an agency, carrier, or software platform, Kallflow adapts to your needs.

Build & Resell Voice Agents

Launch a white-label voice AI agency in days, not months. Maintain full control over pricing and client data.

  • White-label dashboard & branding
  • Team roles & permissions
  • Global webhooks for call lifecycle events
View Agency Pricing
Acme Agency
Live
Active Calls
24
+12%
Agents
156
+8%
This Month
12.4k
+23%
Sub-accounts
3 active
TechStart Inc
45 agents2.1k calls
Global Sales Co
78 agents5.8k calls
Support Plus
33 agents4.5k calls

Product highlights

A focused set of primitives to build, deploy, and scale.

Visual Callflows

Design complex conversation logic with a drag-and-drop builder. Route calls, guide agents, and trigger external APIs.

No-Code
Logic
Routing

Global Webhooks + API

Receive real-time events for every call state change. Control calls programmatically via REST API.

REST
Webhooks
Events

Performance Hub

Monitor latency and agent performance. Drill down into individual call traces for debugging.

Analytics
Traces
Debugging

Audit Logs

Fine-grained permissions for teams plus a complete audit trail of platform and API actions—useful for governance and retention policies.

Permissions
Audit
Governance

Voice + SIP Stack

Connect your SIP provider directly. Bring numbers, trunks, and routing—while you keep control of media paths and storage.

SIP
PSTN
Voice

Client Portal + Billing

Track usage and costs per department or client. Offer a white-label portal and apply custom markups to control your margins.

Portal
Costs
Markup
Deployment

Deploy voice agents
in 3 steps

SIP trunk connected
DID attached
Carrier trunk
sip.acme.tel
TLS/SRTP · OK
Kallflow
Numbers routing
+34…0101 → agent:sales
01

Connect SIP / numbers

Bring your own carrier or SIP trunk, attach numbers, and route calls to agents.

Callflow Builder·draft
Agent
Tools · policy
Action
Create CRM ticket
02

Configure agents + callflows

Define behaviors, tools, and callflows—then assign agents to numbers or routes.

API
Webhook
Endpoint
POST https://acme.dev/webhooks/kallflow
call.startedcall.ended
Payload
{
  "event": "call.ended",
  "call_id": "c_7f3…",
  "duration_s": 128
}
03

Integrate via API + global webhooks

Integrate with your stack using the API and receive events via global webhooks.

Start free. Scale when you're ready.

Self-host for free forever, or let us manage it for you.

Self-hosted
Community
Free forever
Agency
For client workspaces
Scale
Enterprise
Custom infrastructure
PriceFree€99/month€174/monthCustom
AgentsUnlimitedUnlimitedUnlimitedUnlimited
Seats135Unlimited
Client workspaces0515Unlimited
SupportCommunityEmailPriorityDedicated

Enterprise Scale & Compliance

A focused Enterprise package for governance, integrations, and dedicated support—without bloating the landing.

  • Log and event export to your stack: on demand
  • Event streaming: on demand

Scale without limits

No caps on agent slots or concurrency. Add capacity as you grow with dedicated support, custom SLA, and an onboarding team that helps you succeed from day one.

Questions? Answers.

The most common questions about Kallflow Self-hosted.

What does "self-hosted" mean for data/privacy?
Kallflow runs in your infrastructure. You control where call media, logs, and any stored artifacts live, how long they're retained, and who can access them.
What server requirements do I need to host Kallflow?
As a minimum recommendation, you need 8 GB of RAM and 80 GB of disk space. There is no specific CPU cores requirement. Note that these are minimum requirements to get started — if you plan to create many agents or handle many concurrent calls, you'll need to scale resources proportionally.
Do you support SIP trunks and custom carriers?
Yes. You can bring your own carrier and connect SIP trunks, numbers, and routing to voice agents.
Do you support callflows?
Yes. Callflows are built into Kallflow, so you can design multi-step voice flows, route calls, and connect tools or webhooks without building everything from scratch.
What's the difference between self-hosted and cloud?
Self-hosted means you run Kallflow on your own server — full control, zero platform fees, your data never leaves your infrastructure. Cloud means we manage the servers for you — you pay a flat monthly fee and bring your own AI API keys.
What does BYOK mean?
BYOK means "Bring Your Own Keys." In practice, you connect your own API keys for the AI providers you use, and Kallflow does not resell or mark up that usage.
What AI providers does Kallflow work with?
OpenAI, Anthropic (Claude), Google Gemini, Deepgram, ElevenLabs, Cartesia, Azure, and more. You connect your own API keys — Kallflow never marks up your AI costs.
Is AI usage included in the per-minute pricing?
No. The minutes in cloud plans cover managed infrastructure and Kallflow usage, but AI provider usage is billed separately by your providers through your own API keys.
Is there a free trial?
The self-hosted version is completely free, forever. No credit card, no time limit. Deploy it on your own server (min. 8GB RAM) and bring your own AI API keys. If you prefer managed hosting, cloud plans come with a 14-day money-back guarantee.
Feel free to email us: contact@kallflow.com

Start building
for free.

Self-host Kallflow on your own server. No credit card, no time limit, no per-minute fees.