Compare Lab
Fish Audio vs Vapi
Fish Audio is positioned as a developer speech API and creative voice workspace; paid TTS usage is metered in UTF-8 bytes. Vapi is positioned as a developer-oriented orchestration platform for phone and web agents with configurabl
Fish Audio is positioned as a developer speech API and creative voice workspace; paid TTS usage is metered in UTF-8 bytes. Vapi is positioned as a developer-oriented orchestration platform for phone and web agents with configurable providers. Start by deciding who owns the missing layers, then inspect the documented differences below.
Voice Engines and Full Platforms are different product categories. An underlying engine or framework is not a complete substitute for a deployed agent workflow.
22 jointly documented catalog fields. This measures evidence coverage, not equivalent quality or an overall winner.
Test opening hours, booking conflicts and an unanswered transfer.
Start where the records differ.
Values and evidence states are compared together. Shared facts follow the differences; Unknown never means No.
| Decision point | Fish Audio | Vapi |
|---|---|---|
| Billing modelDifferent records | component-stack | platform-plus-pass-through |
| Billing unitDifferent records | TTS: million UTF-8 bytes; ASR: audio hours; Agents: conversation minutes | minute |
| Warm transferDifferent records | Yes | Yes |
| HIPAA pathDifferent records | Unknown | Yes |
| Bring your telephonyShared state | Yes | Yes |
| Bring your modelShared state | Yes | Yes |
Your requirements & next steps
Your requirements
Ready-made / AI receptionist · Strict evidence mode
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TTS uses UTF-8 bytes, ASR audio hours, Agents minutes plus carrier/model/add-ons. Multiple products must not share a fabricated normalized unit.
Reviewed current public offer; retain original billing scope and units.
Free TTS model and Agents promotional basic LLM scope are separate.
Reviewed current public offer; retain original billing scope and units.
Each product keeps its own billing unit.
Reviewed current public offer; retain original billing scope and units.
API access; managed numbers have separate rental and enterprise agreement may differ.
Reviewed current public offer; retain original billing scope and units.
Real sessions consume balance including relevant carrier/model charges; no monthly included minutes.
Reviewed current public offer; retain original billing scope and units.
Destination, transfer and selected model affect cost; no complete ceiling.
Reviewed current public offer; retain original billing scope and units.
Rates have explicit event/destination scope, not a single maximum.
Reviewed current public offer; retain original billing scope and units.
Not yet researched against this buyer-critical field standard.
Reviewed current public offer; retain original billing scope and units.
Call mix, destination, transfer time, selected model/token usage and separate speech products prevent a universal complete monthly/minute ceiling.
Provider choices, tokens, carrier and optional support/compliance fees are not fixed by minutes alone.
Call mix, destination, transfer time, selected model/token usage and separate speech products prevent a universal complete monthly/minute ceiling.
Research conclusion about cost completeness, not a vendor capability.
Anyone with this link can view the encoded decision criteria.
Vendor documentation establishes a claim. Public model benchmarks are separate context, not measurements of these platforms.
Open saved comparison ↗What to verify together.
Fish Audio
UTF-8 bytes and characters are not interchangeable for multilingual scripts.
TTS $15/M UTF-8 bytes; ASR $0.36/audio hour; Agents $0.06/min + applicable surcharges · V3.3 evidence review · TTS API reference; Voice Agents beta has separate minute-based billing
Excluded / confirm: Complete cost cannot be established from this reference. Call mix, destination, transfer time, selected model/token usage and separate speech products prevent a universal complete monthly/minute ceiling. · Phone destination surcharge, $1.20/month managed number, cold $0.015/min or warm $0.025/min post-transfer, non-basic LLM tokens; BYO carrier separate
TTS uses UTF-8 bytes, ASR audio hours, Agents minutes plus carrier/model/add-ons. Multiple products must not share a fabricated normalized unit.
Vapi
The $0.05 hosting charge is only one component of the call bill.
$0.05/min Vapi hosting · V3.3 evidence review · Hosting only; model, speech, carrier and compliance/support add-ons extra
Excluded / confirm: Complete cost cannot be established from this reference. Provider choices, tokens, carrier and optional support/compliance fees are not fixed by minutes alone. · LLM, transcriber, voice and carrier charges; HIPAA add-on $2,000/month
Reviewed current public offer; retain original billing scope and units.
The evidence overlap.
Both records have documented values for Product type, Call direction, Technical setup, Pricing model, Published numeric pricing, SIP trunking, Bring your telephony, Call recording, Realtime / streaming audio, Bring your model, Knowledge base / RAG, Function / tool calling and additional fields shown in Compare. Matching availability does not measure behavior under your call conditions.
Run the same booking, tool failure and unsuccessful human-transfer cases. Record both outcomes and billable units before signing a deployment agreement.
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