Retell AI vs Vapi

Retell AI

Audio

Vapi

Audio

Tagline

Retell AI

Build, test and deploy production-grade AI voice agents for inbound and outbound calls.

Vapi

Developer platform for building, deploying, and scaling production voice AI agents

Pricing

Retell AI

Freemium· from $0.07/mo

Vapi

Freemium· Free tier · from $29/mo

Lowest paid tier

Retell AI

$0.07-$0.31 / min · Pay as you go

captured 2026-10-21

Vapi

$29 / month · Core

captured 2026-10-12

Free trial

Retell AI

Yes

Vapi

Yes

API

Retell AI

Yes

Vapi

Yes

Hacker News stories

Retell AI

1

checked 2026-10-20

Vapi

3

checked 2026-10-22

Earliest Wayback capture

Retell AI

2024-02-21

earliest archived capture of the site, not a launch date

Vapi

—

Model used

Retell AI

LLM-agnostic (OpenAI, Anthropic, Google and others selectable per agent); proprietary turn-taking model and voice pipeline in-house

Vapi

Model-agnostic: OpenAI GPT-4o, Anthropic Claude, Google Gemini, Groq, DeepSeek, Llama; STT/TTS via Deepgram, ElevenLabs, PlayHT, Cartesia, Azure

Best for

Retell AI

Product and CX teams building production voice agents for high-volume inbound support or outbound sales — especially in healthcare, insurance, financial services and logistics where compliance, low latency and CRM/telephony integrations matter.

Vapi

Product and engineering teams building voice agents for phone-based support, sales, or scheduling who want control over the model stack without engineering the real-time voice pipeline themselves.

Not for

Retell AI

Hobbyists prototyping a text-only chatbot, teams that need fully self-hosted or open-source voice stacks, or low-volume use cases where per-minute pricing outweighs the convenience of a managed platform.

Vapi

Non-technical operators looking for a fully packaged, no-code IVR replacement, or hobbyists who need a truly free tier with predictable flat pricing.

Editorial score

Retell AI

—

Vapi

—

Use cases

Retell AI

AI inbound call answeringOutbound lead qualificationAppointment scheduling and remindersCollections and payment dialers24/7 customer support triageIVR replacementHealthcare intake and follow-up callsInsurance claims first-notice-of-lossVoice-enabled RAG knowledge assistantsChat and SMS agents sharing a voice knowledge base

Vapi

AI phone receptionistOutbound lead qualification callsAppointment scheduling and remindersVoice-based customer supportOrder taking and reservationsIVR replacementVoice-driven surveys and market researchDebt collection and payment remindersInsurance intake callsVoice interface for internal tools

Pros

Retell AI

• Sub-second end-to-end latency (~600 ms) with a purpose-built turn-taking model — conversations feel natural rather than walkie-talkie.
• Batteries-included telephony: bring Twilio/Vonage/Telnyx/Amazon Connect or use Retell-provisioned numbers with SIP trunking.
• Real function calling for booking, transfers, payments and CRM writes, with pre-built HubSpot, Salesforce, Cal.com, n8n, Zapier and Make integrations.
• Streaming RAG knowledge base with auto-sync, plus simulation testing and continuous QA — the operational glue most DIY voice stacks skip.
• Enterprise compliance out of the box: HIPAA, SOC 2 Type II, GDPR, PII removal and safety guardrails as toggleable add-ons.
• Genuinely transparent pay-as-you-go pricing with a $10 starter credit, so you can benchmark cost per call before committing.

Vapi

• Model-agnostic stack lets you swap LLM, STT, and TTS providers per assistant and bring your own API keys
• Handles the real-time voice plumbing (interruption detection, endpointing, barge-in, backchanneling) that is painful to build from scratch
• First-class REST API and SDKs across Node, Python, Web, iOS, Android, Flutter, and React Native
• Built-in telephony: provisions phone numbers, supports SIP trunks, and covers inbound and outbound calls
• Tool/function calling and 25+ prebuilt integrations (Salesforce, HubSpot, Zapier, Make, Cal.com, etc.) for real workflows
• Enterprise compliance path: SOC 2, HIPAA (add-on), PCI, SSO, RBAC, Zero Data Retention available
• Transparent per-minute platform fee with model costs passed through at cost rather than marked up opaquely

Cons

Retell AI

• Per-minute costs stack quickly once you enable QA ($0.10/min), knowledge base, denoising and premium LLMs — a 'cheap' agent can land near $0.30+/min.
• The specific LLMs are pluggable but Retell doesn't publish a default recommendation, so cost/quality tuning is on you.
• Not open source and there is no self-hosted option — regulated buyers who need on-prem inference are out of scope.
• Voice/telephony focus means it is overkill (and overpriced) for pure text chatbots you could run on a generic LLM API.
• True enterprise features (unlimited concurrency, custom compliance, dedicated support) require a sales conversation, not a self-serve upgrade.

Vapi

• Total cost is hard to predict because platform fee, LLM, STT, TTS, and telephony are billed separately and stack up
• HIPAA compliance and Zero Data Retention are paid add-ons ($2,000/mo and $1,000/mo) rather than included
• Latency and voice naturalness ultimately depend on the third-party providers you choose, not Vapi itself
• Build plan retains call history only 14 days and chat history 30 days, so long-term analytics require your own pipeline
• Not a no-code tool — meaningful agents still require prompt engineering, tool wiring, and webhook code
• Concurrency beyond 10 lines costs $10/line/month, which adds up for high-volume outbound campaigns

Website

Retell AI

www.retellai.com

Vapi

vapi.ai

Editorial score: rule-based, 0–10, from AI-assisted profile inputs (see /methodology) — not a user rating; “—” means unscored. “Not listed” means we have no record of it, not that it is absent. GitHub figures and prices carry the date they were checked or captured; prices are shown as published, unconverted.