Omnia Voice vs Vapi

Vapi is a developer platform for building voice agents, and a good one. API-first, strong documentation, a large community, and plenty of third-party examples. If you want to choose every component yourself and wire them together, that is exactly what it is for.

Omnia is built the other way round. This page is about what that difference actually means.

Choose Vapi if

• You want to pick each piece yourself — a specific speech-to-text model, a specific LLM, a specific voice vendor — and own how they fit together
• You want the largest ecosystem and the most community examples
• You are comfortable with cost being a function of that assembly
• Hosted-only suits you

Those are real advantages. If they describe you, Vapi is the right tool.

Choose Omnia if

• You want a cost you can forecast before you run traffic
• You want one system rather than five you assemble
• You need to run it on your own infrastructure, or keep audio in the EU

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What a call costs

The difference here is structural, not a question of who is cheaper.

Vapi charges a platform rate, and then the pieces you assemble on top meter separately — speech-to-text, the language model, text-to-speech, and telephony, each from its own vendor at its own price. The figure on the pricing page is the platform. The invoice is the platform plus four other things.

That is the honest consequence of a modular design, and modularity is the point of Vapi. It also means you cannot put a number in a forecast until you have run real traffic, and that your unit economics move whenever one of those vendors reprices.

Omnia charges one rate for the AI:

One number covering speech recognition, reasoning and speech synthesis, because they are not separate purchases.

The first two rates are self-serve: sign up and start. The volume rate is negotiated rather than unlocked automatically, so talk to us if you are running at scale.

Telephony is not included, and we do not resell it. Bring Twilio, Telnyx, Setera or a SIP trunk you already have, and pay them their rates directly. Your phone bill stays your phone bill, at whatever you already negotiated.

We would rather say that plainly than claim "all-inclusive" and let you find the asterisk later.

One system, not five

Vapi's flexibility comes from letting you assemble the stack. The cost of assembly is that you own the seams — the latency where the pieces meet, the failure modes when one is slow, and the debugging when a caller is misheard and you have to work out which stage lost them.

Omnia connects audio directly to the reasoning layer. There is no speech-to-text stage in the middle, which is where the round-trip time goes and where nuance gets dropped. That single design decision produces two things worth having:

Speed. About 250 milliseconds to first response, because processing starts while the caller is still speaking rather than after a transcript is finished.

Robustness. Accents, proper nouns, and callers who switch language mid-sentence survive, because there is no transcription step to flatten them first. In practice that is what 50+ languages means — not a list on a pricing page, but comprehension over a narrowband phone line, in Finnish or Spanish, at conversational pace.

Agents that act

Both platforms support tools. Worth knowing what ours carry:

• Credentials encrypted at rest, decrypted only while a single call's payload is assembled, never returned by the API
• Static parameters the model never sees — tenant IDs and account scoping a caller cannot talk the agent out of
• Read-only tools run eagerly while the agent is still speaking, so a lookup does not become dead air
• A deferred pattern for work that cannot finish inside the timeout, without stranding the caller in silence

Table-stakes function calling is table stakes. The details above are what decides whether an agent is usable on a real phone line.

Where it runs

Vapi is hosted. That is the product, and for most teams it is the right answer.

Omnia runs three ways on the same API — our cloud, dedicated GPU capacity, or entirely your own infrastructure, cloud or on-premise. Moving between them does not change your integration code. EU data residency is the default rather than a configuration.

Self-hosting is also an exit route, not only a deployment preference. If we were acquired, pivoted, or sunset a service, a self-hosted customer keeps running. You cannot be orphaned by us. A hosted-only platform cannot make that offer, by construction.

Who runs this

Veikkaus, Elisa, Eltel Networks and MySpeaker run on Omnia in production, and our partners deliver it for their own clients — Nitor for Finnair, Posti and OP Financial Group; Houston Inc. for Telia and Wärtsilä. Setera provides the telephony layer beneath, across more than fifty countries.

Side by side

Migrating

Both model the same primitives: an agent with a prompt, a voice, tools, and a way to reach it. Moving usually means recreating the agent configuration, repointing your tool webhooks — the shapes differ, the concepts do not — and pointing your existing carrier at a new WebSocket URL.

Your phone numbers do not move, because they were never ours to hold.

The honest summary

If you want to choose every component and own the stack you assemble, Vapi gives you that and a larger community to do it with.

If you would rather have one system with a cost you can put in a forecast, that runs where you need it to run and copes with callers who do not all sound the same — that is the trade we made.