Methodology
How we check every price and ranking
Cozzo exists to help you pick the right voice AI stack, so the numbers have to be right. Here’s exactly where they come from, how the finder scores tools, and when each vendor was last checked.
- vendors with verified pricing
- 53
- re-checked since October 14
- 23
- voice models tracked
- 22
- models in the cost calculator
- 11
Where prices come from
- Every price, plan limit and feature comes from the vendor’s own pricing page or official docs. Each tool page links to that exact source.
- We don’t use review sites, reseller pages, press coverage or sales calls as a source for numbers.
- If a vendor only sells through quotes, we say “Quote only” and describe the billing model instead of estimating a price.
- If we can’t verify a current price, the product is left out of price tables rather than guessed. PlayHT, for example, isn’t in the model table for that reason.
How we keep it fresh
- Vendors are re-checked on a rolling basis, with the most-compared platforms and speech APIs checked most often.
- Each tool page shows its own “last verified” date, and the full log is below.
- When a vendor changes a price, we update the listing, its comparisons and its guides together so the site never disagrees with itself.
- Vendors change prices without notice, so always confirm on the source page before you buy.
How the finder scores tools
The voice model finder is a transparent, rule-based score, not a black box and not a paid ranking. Each answer adds or removes points:
| Signal | Points | Notes |
|---|---|---|
| Use case matches | +50 | A tool built for a different job is dropped (−100). |
| Speech API type matches (STT, TTS, speech-to-speech) | +10 to +15 | A vendor without a verified model of that type is dropped. |
| Technical skill fits (no-code or developer) | +20 | A mismatch costs −15. |
| Monthly call volume fit | 0 to +15 | Set per tool from its published plan limits and per-minute pricing. |
| Language support verified | +10 (Spanish) / +15 (many) | Only languages the vendor documents count. |
| Your top priority (speed, voice, cost) | +15 | Tags come from verified latency, voice and price data. |
Tools with a total of zero or less are hidden. Ties are broken alphabetically, so the same answers always return the same order. The finder also shows the next three tools and the main reason each one scored lower.
What the cost calculator includes
- The cost calculator only uses models whose official price is stated per minute or per hour (11 today). Hourly prices are divided by 60.
- Character-, token- and credit-priced models aren’t converted to per-minute costs, because that would need assumptions about speaking speed and conversation length.
- Prices marked with “~” are approximate on the vendor’s own page, and we keep that marking.
- Telephony, phone numbers, concurrency add-ons and taxes are billed separately by most vendors. Check each tool’s pricing breakdown for those line items.
Independence
- Nobody pays to be listed, to rank higher in the finder, or to win a comparison.
- Sponsored placements always carry a “Sponsored” label, sit outside rankings and use rel="sponsored". If we ever add affiliate links, we’ll disclose them where they appear.
- Read the full editorial policy.
Verification log
Every vendor with verified pricing, newest check first.
| Vendor | Category | Last verified | Source |
|---|---|---|---|
| Bland AI | Voice Agent Platforms | bland.ai ↗ | |
| Cartesia | Speech-to-Text & Text-to-Speech | cartesia.ai ↗ | |
| Deepgram | Speech-to-Text & Text-to-Speech | deepgram.com ↗ | |
| Dialzara | AI Receptionists for SMBs | dialzara.com ↗ | |
| ElevenLabs Agents | Voice Agent Platforms | elevenlabs.io ↗ | |
| Goodcall | AI Receptionists for SMBs | goodcall.com ↗ | |
| LiveKit Agents | Open-Source & Dev Frameworks | livekit.com ↗ | |
| My AI Front Desk | AI Receptionists for SMBs | myaifrontdesk.com ↗ | |
| Phonely | AI Receptionists for SMBs | phonely.ai ↗ | |
| Pipecat | Open-Source & Dev Frameworks | daily.co ↗ | |
| Plivo | Telephony & Phone Numbers | plivo.com ↗ | |
| Retell AI | Voice Agent Platforms | retellai.com ↗ | |
| Rime | Speech-to-Text & Text-to-Speech | rime.ai ↗ | |
| Rosie | AI Receptionists for SMBs | heyrosie.com ↗ | |
| Smith.ai | AI Receptionists for SMBs | smith.ai ↗ | |
| Soniox | Speech-to-Text & Text-to-Speech | soniox.com ↗ | |
| Speechmatics | Speech-to-Text & Text-to-Speech | speechmatics.com ↗ | |
| Telnyx | Telephony & Phone Numbers | telnyx.com ↗ | |
| Trillet | Voice Agent Platforms | trillet.ai ↗ | |
| Twilio | Telephony & Phone Numbers | twilio.com ↗ | |
| Ultravox | Voice Agent Platforms | ultravox.ai ↗ | |
| Vapi | Voice Agent Platforms | vapi.ai ↗ | |
| Hume AI | Speech-to-Text & Text-to-Speech | dev.hume.ai ↗ | |
| AssemblyAI | Speech-to-Text & Text-to-Speech | assemblyai.com ↗ | |
| Bolna | Voice Agent Platforms | bolna.ai ↗ | |
| Botpress | Voice Agent Platforms | botpress.com ↗ | |
| Cekura | Testing & QA | cekura.ai ↗ | |
| Cognigy | Enterprise Customer Service | docs.cognigy.com ↗ | |
| Coval | Testing & QA | coval.ai ↗ | |
| Dasha | Voice Agent Platforms | dasha.ai ↗ | |
| Decagon | Enterprise Customer Service | decagon.ai ↗ | |
| Gemini Live API | Open-Source & Dev Frameworks | ai.google.dev ↗ | |
| Gladia | Speech-to-Text & Text-to-Speech | gladia.io ↗ | |
| Hamming | Testing & QA | hamming.ai ↗ | |
| Hyperbound | Sales & Outbound | hyperbound.ai ↗ | |
| Lindy | AI Receptionists for SMBs | lindy.ai ↗ | |
| Loman | AI Receptionists for SMBs | loman.ai ↗ | |
| Millis AI | Voice Agent Platforms | millis.ai ↗ | |
| Numa | AI Receptionists for SMBs | numa.com ↗ | |
| OpenAI Realtime API | Open-Source & Dev Frameworks | developers.openai.com ↗ | |
| Parloa | Enterprise Customer Service | parloa.com ↗ | |
| PolyAI | Enterprise Customer Service | poly.ai ↗ | |
| Regal | Sales & Outbound | regal.ai ↗ | |
| Resemble AI | Speech-to-Text & Text-to-Speech | resemble.ai ↗ | |
| Sierra | Enterprise Customer Service | sierra.ai ↗ | |
| Slang.ai | AI Receptionists for SMBs | slang.ai ↗ | |
| Synthflow | Voice Agent Platforms | synthflow.ai ↗ | |
| Thoughtly | Voice Agent Platforms | thoughtly.com ↗ | |
| Vocode | Open-Source & Dev Frameworks | github.com ↗ | |
| Vogent | Voice Agent Platforms | docs.vogent.ai ↗ | |
| Voiceflow | Voice Agent Platforms | voiceflow.com ↗ | |
| Vonage | Telephony & Phone Numbers | vonage.com ↗ | |
| Voximplant | Voice Agent Platforms | voximplant.com ↗ |
Spotted something out of date?
Corrections are welcome. See the about page for how to reach us, and include the vendor’s source link so we can re-check it quickly.