Ultravox
Realtime speech model + platform
From $0.05/min
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What we know about Ultravox
Ultravox is a voice ai platform: realtime speech model + platform. This profile tracks what we have verified about Ultravox, each fact linked to a primary source and dated.
On pricing, Ultravox starts at $0.05 per minute for its entry tier. That is the sticker rate: real production cost usually runs higher once you add a language model, a voice provider, and telephony minutes, and we model Ultravox closer to 0.055-0.055 USD/min all-in. Every Ultravox comparison on the site works from that all-in figure rather than the headline number, because the headline number is rarely what the invoice says.
New Ultravox accounts get 30 minutes free, then $0.05/min to test with before a card is required, which is enough to run a handful of real calls and judge latency and voice quality for your own script rather than a demo.
On capabilities, Ultravox covers native sip trunking, bring-your-own tts voice, native outbound campaigns, warm transfer to human, built-in knowledge base, and dtmf / ivr navigation, and does not offer annual contract required for best pricing?, bring-your-own llm, and interruption handling (barge-in). Each of those is verified against Ultravox's own docs or dashboard, not marketing copy.
On performance, Ultravox reports 5 calls concurrent calls on the base plan. Latency figures are vendor claims until we measure them ourselves, and they are labeled that way on the Ultravox fact sheet, so treat them as a starting point rather than a guarantee.
In total we track 23 verified facts for Ultravox today, and add coverage as the ingestion pass revisits it. Where a number is a vendor claim rather than our own measurement, it is labeled as such on the Ultravox fact sheet below, and each row links the primary source it came from so you can check our work.
Whether Ultravox is the right call depends on your use case more than any single spec, which is why the head-to-head verdicts below score it per scenario rather than crowning one overall winner. Use the fact sheet for the raw numbers, and the matchups for how Ultravox actually fares against the platforms buyers most often weigh it against.
Fact sheet
Every row independently verifiedConsidering a switch? Best Ultravox alternatives →
TTS in this stack
Ultravox lets you bring your own text-to-speech voice, so the voice engine is a separate pricing and quality decision. Compare the engines builders plug in most: ElevenLabs, Cartesia, OpenAI TTS, or the full text-to-speech comparison →