Deepgram vs Ultravox.ai

Deepgram

Deepgram is the pick when you are building the pipeline yourself and the per-minute number matters: streaming Nova-3 at under half a cent a minute, published rates for every model and mode, and a $200 credit that does not expire make it easy to size a bill before signing anything. It is an API, not a product — there is no transcription app to hand to a non-developer, and the voice agent tier is priced per connected minute, so idle sessions cost money.

Pros

• +Rates are public down to a fraction of a cent, per model and per mode
• +$200 starting credit with no card and no expiry is enough to benchmark seriously
• +Streaming and batch share one API, and the Voice Agent API saves wiring STT, LLM and TTS together
• +Founded 2015 and Series C funded, with self-hosted deployment on enterprise terms

Cons

• −Streaming rates are marked as limited-time promotional, so the published number may rise
• −Voice Agent minutes are billed on WebSocket connection time, including silence
• −Growth pricing starts at a $4,000 annual prepay, with nothing between pay-as-you-go and that

Ultravox.ai

One of the few voice stacks where the model itself is the product rather than glue over someone else's transcriber, and the open weights on Hugging Face mean you are not locked into the hosted service. Skipping the speech-to-text hop is the whole point — latency and prosody both benefit. It is a builder's tool, not a no-code agent designer, so budget engineering time as well as per-minute cost.

Pros

• +Model takes audio directly, removing the transcription hop from the response path
• +Open-weight models published on Hugging Face allow self-hosting
• +REST API plus web and mobile SDKs, and SIP for phone calls
• +RAG corpora and custom voices are part of the platform, not add-on services
• +Pay as you go has no monthly floor, so a prototype costs only what it talks

Cons

• −Free tier is limited to 5 concurrent calls, so load testing needs a paid plan
• −Custom voices and RAG corpora are capped even on the $100 Pro tier
• −Threads bill separately per token on top of per-minute conversation cost
• −Requires real engineering; there is no visual flow builder

Is Deepgram cheaper than Ultravox.ai?

On published entry prices, Deepgram starts lower — $0.0043/min against $0.05/min for Ultravox.ai. Entry price is the lowest paid plan as we last verified it; what each plan includes differs.

Does Deepgram or Ultravox.ai have a free tier?

Both: Deepgram has a free tier, and Ultravox.ai has a free tier.

Which has a public API, Deepgram or Ultravox.ai?

Both ship a public API, so either can be built on; the fact table above shows the platforms each one runs on.