Ultravox
Infrastructure for real-time voice agents, with usage-based calling, custom voices, and RAG support.
About Ultravox
Ultravox is a real-time, speech-native voice AI infrastructure layer for teams building conversational agents. The service includes concurrent calling, custom voice clones, outbound scheduling, and corpora for retrieval-augmented generation. Pay As You Go costs $0.05 per minute and allows up to five concurrent calls, one custom voice, and two RAG corpora. Pro costs $100 per month plus the same per-minute usage rate, removes the hard concurrency cap, and expands voice and corpus limits. Enterprise pricing is custom and adds organization support and a priority SLA. Separate SIP and language-model token charges affect total cost. The service processes voice recordings, transcripts, interaction data, and uploaded knowledge-base content, which affects privacy and data-governance requirements.
Best for
Best use cases
Handle inbound voice conversations with low-latency agents
Schedule outbound calling campaigns on Pro
Ground spoken answers in connected RAG corpora
Compare before choosing
Pay As You Go has a five-call concurrency cap; Pro has no hard cap
Pro raises custom voices from one to five
Pro raises RAG corpora from two to twenty
Features
Real-time voice agents
Build speech-native agents designed for fast, natural conversations without stitching together separate speech components.
Outbound call scheduling
Schedule outbound calls on the Pro plan, which suits teams running proactive calling workflows.
Custom voices
Use one custom voice clone on Pay As You Go or five on Pro to give agents a consistent voice.
RAG corpora
Connect up to two corpora on Pay As You Go or twenty on Pro for knowledge-grounded conversations.
Pros
- Usage-based entry at $0.05 per minute makes small deployments easier to budget.
- Pro removes the hard concurrency cap and adds outbound scheduling for scaled calling workflows.
- Custom voices and RAG corpora are included across paid tiers, with higher limits on Pro.
Cons
- Pro costs $100 per month before per-minute usage, SIP, and language-model token charges.
- Pay As You Go limits concurrent calls to five, which can constrain busy production workloads.
- Voice recordings, transcripts, interaction data, and uploaded knowledge-base content require a careful privacy review.
Pricing Plans
Pay As You Go
- 30 included minutes
- SIP at 0.5¢ per minute
- Up to 5 concurrent calls
- 1 custom voice clone
- 2 corpora for RAG
- Unlimited Playground
Pro
- $0.05 per minute
- 30 included minutes
- SIP at 0.48¢ per minute
- No hard concurrency cap
- Outbound Call Scheduler
- 5 custom voices
- 20 corpora for RAG
Enterprise
- Custom usage and SIP pricing
- Priority SLA
- Organization support
- Custom configuration
- Unlimited Playground
* Pricing information is for reference only. Please refer to the latest announcement on Ultravox's official website.