kitio.aiAdded Oct 29, 2026
Ultravox
Freemium · $100/moSpeech-native voice AI platform for real-time voice agents
What is Ultravox?
Ultravox is a developer platform for building real-time voice agents on a speech-native model that processes audio directly instead of converting it to text first. It is aimed at teams that need fast, natural phone and app conversations, and offers APIs plus a playground.
The company argues that transcribing speech first adds latency and loses tone, cadence and pitch, so it trains its own model and runs it on dedicated infrastructure. The platform covers agent calls, an outbound call scheduler, custom voices and SIP connectivity.
The homepage notes that Ultravox has been acquired by Inworld to speed up its speech-to-speech research and voice agent work. Pricing is per minute of calls, with a free allowance and a monthly Pro plan that removes concurrency caps.
Features
- Speech-native model
- Real-time voice agents
- Outbound call scheduler
- Custom voices
- SIP support
Tags
Releases
+ Submit new release- Listed
Ultravox was added to the directory.
Organization
Ultravox (Inworld)
🇺🇸 United States
Listed by kitio.ai · unverified owner
Pricing
- Pricing model
- Freemium
- Paid options from
- $100/mo
- Billing frequency
- Monthly
Ultravox plans
Pay as you go
$0.05 / minute
- 30 free minutes of calls
- Up to 5 concurrent calls
- Unlimited playground calls
Pro
$100/mo
- No hard concurrency caps
- Outbound call scheduler
- 5 custom voices
Enterprise
Custom
- Custom pricing
- Volume rates
Prices in USD, checked Oct 29, 2026. Plans change often, so confirm on the Ultravox site.Official pricing
Sponsored
Your AI tool here
A Featured launch puts your tool in this spot and on the home page for a week.
Top Ultravox alternatives
View allModels & APIs
Emotionally intelligent voice AI, expression APIs and voice evals
Models & APIs
Free playground and API keys for Google's Gemini and Gemma models
Models & APIs
Anthropic's developer platform and API for building with Claude models
Models & APIs
Developer API for GPT, reasoning, image, audio and embedding models
Compare Ultravox
If you liked Ultravox
Speech-to-text, text-to-speech and voice agent APIs for developers
FreemiumAudio & voiceMade in United StatesLow-latency text-to-speech API for voice agents
Freemium · $5/moAudio & voice5 clicks to the websiteMade in United StatesDeveloper platform to build, test and deploy voice AI agents
Freemium · $29/moCustomer supportMade in United StatesLow-latency text-to-speech and speech-to-text models for voice apps
Freemium · $5/moAudio & voiceMade in United States
Pros and cons
Pros
- Skips the speech-to-text step
- 30 free minutes to start
- Unlimited playground calls
Cons
- Developer-focused, not a no-code tool
- Pay-as-you-go plan limits concurrent calls to 5
- Now part of Inworld, so the roadmap may shift
Prompts & results
No prompts yet. Add your own prompt and output to help others use this tool.
Share a prompt
Reviews
Q&A
What is Ultravox?
Ultravox is a developer platform for building real-time voice agents on a speech-native model that processes audio directly instead of converting it to text first. It is aimed at teams that need fast, natural phone and app conversations, and offers APIs plus a playground.
How is Ultravox priced?
Calls cost $0.05 per minute after the first 30 free minutes. The Pro plan adds a monthly fee and removes the hard concurrency cap.
Who owns Ultravox now?
The homepage says Ultravox has been acquired by Inworld to accelerate speech-to-speech research and voice agent capabilities.
How much does Ultravox cost?
Ultravox is freemium, with paid plans from $100/mo.
Is there a free version of Ultravox?
Yes. Ultravox has a free plan, and paid plans add more usage and features.
What are the main features of Ultravox?
Speech-native model, Real-time voice agents, Outbound call scheduler, Custom voices, SIP support.
Who makes Ultravox?
Ultravox is made by Ultravox (Inworld).
What are the best alternatives to Ultravox?
Popular alternatives include Hume AI, Google AI Studio, Claude Platform.