What is the best free alternative to Ultravox?
LiveKit Agents is the closest free alternative to Ultravox: same Real-Time Voice Agents sub-category, and it is free. Apache-2.0 open-source framework, fully self-hostable on your own servers
Best free Ultravox alternatives
Looking for a free alternative to Ultravox? Here are 9 real-time voice agents worth trying — 9 with a free tier. Ultravox itself is free tier + paid.
| Tool | Ultravox (you searched) | LiveKit Agents | Pipecat | Vapi |
|---|---|---|---|---|
| Pricing | freemium | free | free | freemium |
| Best for | Speech-native processing skips the STT-to-text bottleneck, preserving tone/cadence/pitch | Apache-2.0 open-source framework, fully self-hostable on your own servers | BSD-2-Clause open-source Python framework for real-time voice/multimodal agents | Orchestrates STT/LLM/TTS providers of choice into one low-latency voice-agent pipeline |
| Visit | Open ↗ | Open ↗ | Open ↗ | Open ↗ |
Ultravox alternatives — straight answers
Are there free Ultravox alternatives?
Yes — 9 of the 9 alternatives listed here are free or freemium: LiveKit Agents, Pipecat, Vapi, Retell AI, Bland AI. None of them are paid-only.
Is Ultravox free?
Ultravox is free tier + paid. There is a free tier you can work in, with paid plans above it.
How were these Ultravox alternatives chosen?
They are the other tools in Real-Time Voice Agents, then the rest of AI Agents & Automation, ordered free tiers first and capped at 9. There is no sponsorship and no paid placement in that ordering — only the pricing tier decides.
All Ultravox alternatives
Browse Real-Time Voice Agents →LiveKit Agents
Real-Time Voice Agents
✦ WhyA Ultravox alternative — Apache-2.0 open-source framework, fully self-hostable on your own servers.
- Apache-2.0 open-source framework, fully self-hostable on your own servers
- Native WebRTC client support across web/mobile/telephony out of the box
- Native Model Context Protocol (MCP) support for tool-using voice agents
Pipecat
Real-Time Voice Agents
✦ WhyA Ultravox alternative — BSD-2-Clause open-source Python framework for real-time voice/multimodal agents.
- BSD-2-Clause open-source Python framework for real-time voice/multimodal agents
- Supports distributed multi-agent systems with handoffs over a shared bus
- Maintained by Daily with an active plugin ecosystem for STT/LLM/TTS providers
Vapi
Real-Time Voice Agents
✦ WhyA Ultravox alternative — Orchestrates STT/LLM/TTS providers of choice into one low-latency voice-agent pipeline.
- Orchestrates STT/LLM/TTS providers of choice into one low-latency voice-agent pipeline
- Usage-based per-minute pricing with free trial minutes included
- SOC 2/HIPAA/PCI compliance add-ons for regulated call-center deployments
Retell AI
Real-Time Voice Agents
✦ WhyA Ultravox alternative — Free starting credit with no contract required.
- Free starting credit with no contract required
- Supports swapping GPT, Claude or Gemini as the reasoning layer per agent
- Batch calling campaigns plus live AI-to-human call transfer built in
Bland AI
Real-Time Voice Agents
✦ WhyA Ultravox alternative — All-in-one per-minute pricing bundles LLM+STT+TTS with no separate token pass-through charges.
- All-in-one per-minute pricing bundles LLM+STT+TTS with no separate token pass-through charges
- Free start with call credits plus an inbound number included
- Tiered platform fees (Build/Scale) unlock lower per-minute rates for high volume
Zhipu AutoGLM
General Autonomous Agents
✦ WhyA Ultravox alternative — Free foundation-agent system for autonomous GUI control (web + Android).
- Free foundation-agent system for autonomous GUI control (web + Android)
- Voice-to-action: controls entire web/phone UI from a spoken instruction
- AutoGLM Rumination adds deep-research style multi-step task execution
Windmill
Workflow Automation
✦ WhyA Ultravox alternative — Open-source, self-hostable with unlimited executions on the free tier.
- Open-source, self-hostable with unlimited executions on the free tier
- Turns scripts (Python/TS/Go/Bash/SQL) into flows and full internal apps
- Kubernetes/Docker/Fargate deployable with a hybrid seat+compute enterprise pricing model
Langflow
Workflow Automation
✦ WhyA Ultravox alternative — Open source with 138k GitHub stars, free desktop app and free cloud account.
- Open source with 138k GitHub stars, free desktop app and free cloud account
- Drag-and-drop visual builder for agents and RAG pipelines on top of LangChain primitives
- Deep integrations across major LLMs, vector DBs and Google Cloud/Slack/MongoDB
LangGraph
Agent Frameworks (Developers)
✦ WhyA Ultravox alternative — Build stateful, multi-agent apps as graphs.
- Build stateful, multi-agent apps as graphs
- Human-in-the-loop and durable execution
- Works with any LLM
- Open-source with a hosted platform