本番環境向け音声AIエージェントインフラ — スケール可能なインバウンド、アウトバウンド、IVR代替AIエージェントを構築できます。
音声ツール利用メモリ
Retell AI vs Synthflowwhich AI support agent should you pick in 2026?
Production voice agent platform — LLM-native phone agents with low-latency streaming and per-minute pricing.
VoiceTool useMemory
Retell AI vs Synthflow — specs
| Spec | Retell AI | Synthflow |
|---|---|---|
| Agent Rank | 73 / 100 (A) | 77 / 100 (A) |
| Autonomy | Autonomous | Autonomous |
| Pricing | Pay per task · Free tier | Freemium · from $29 |
| Open source | No | No |
| Capabilities | Voice, Tool use, Memory | Voice, Tool use, Memory |
| Integrations | 3 apps | 4 apps |
| Verified | Verified | Verified |
| Released | Mar 2025 | Feb 2025 |
Agent Rank breakdown
Retell AI
Agent Rank
73/ 100
- 自律性
- 9
- 機能
- 6
- 連携
- 4
- 料金
- 9
- 完成度
- 6
- 検証性
- 10
自律性、機能、連携、料金、成熟度、編集部の検証を基に自動算出。デプロイごとに更新されます。 どのように算出されているか?
Synthflow
Agent Rank
77/ 100
- 自律性
- 9
- 機能
- 6
- 連携
- 8
- 料金
- 7
- 完成度
- 6
- 検証性
- 10
自律性、機能、連携、料金、成熟度、編集部の検証を基に自動算出。デプロイごとに更新されます。 どのように算出されているか?
Pros & cons
Retell AI
メリット
- +Lowest per-minute pricing among production voice agent platforms
- +Strong streaming latency (~300ms) competitive with ElevenLabs
- +Per-minute pricing easier to forecast than per-seat
デメリット
- −Less polished out-of-the-box than Synthflow for non-technical buyers
- −Documentation and tooling still maturing vs ElevenLabs
- −Voice quality varies by model selection
Synthflow
メリット
- +Truly no-code — non-developers can ship a working voice agent in an afternoon
- +Templates cover most common voice-agent use cases (appointment scheduling, lead qual, surveys)
- +White-label option lets agencies resell to clients
デメリット
- −No-code abstractions can hit ceilings for advanced logic
- −Voice quality slightly behind ElevenLabs-based stacks
- −Pro tier pricing is steep at $375/mo for 1,500 minutes
Pricing
Retell AI
Pay-as-you-go
無料
Developers
- +~$0.07/min
- +Production-ready API
おすすめ
Scale
カスタム
High-volume voice ops
- +Volume discounts
- +Dedicated infrastructure
- +Custom models
Synthflow
Starter
$29/月
Solo users
- +50 minutes
- +Basic templates
おすすめ
Pro
$375/月
Growing teams
- +1,500 minutes
- +CRM integrations
- +Outbound campaigns
Growth
$900/月
Heavy ops
- +3,500 minutes
- +Custom voice cloning
- +White-label option
Enterprise
カスタム
Large ops
- +Custom volumes
- +Dedicated CS
- +SSO
Which one should you pick?
Synthflow
Pick Synthflow if its specific capabilities (Voice, Tool use) match what you need.
Try Synthflow →Affiliate links. We may earn a commission at no extra cost to you.
Frequently asked
Should I pick Retell AI or Synthflow in 2026?+
Pick Retell AI if cost is the main constraint. Pick Synthflow if its specific capabilities (Voice, Tool use) match what you need. Most working teams running both can use Retell AI for primary work and Synthflow for the workflows where its specific strengths matter.
What's the price difference between Retell AI and Synthflow?+
Retell AI starts at Pay per task · Free tier; Synthflow starts at Freemium · from $29. Retell AI is the cheaper entry option. For team deployments the TCO can differ — use the AI Agent Rank TCO calculator for your specific volume.
Which is more autonomous, Retell AI or Synthflow?+
Both Retell AI and Synthflow are Autonomous agents — neither has a meaningful autonomy advantage over the other. The decision should hinge on capabilities and pricing instead.
Readers comparing Retell AI and Synthflow also picked
Adjacent agents in the same category with overlapping capabilities — worth a side-by-side glance before you commit.
Conversational Agents を備えたAI音声プラットフォーム — プロダクションレベルの音声クローニング、TTS、および音声エージェント。
音声ツール利用メモリDemo · hover to playコールセンター向けエンタープライズ音声アシスタント — 自然な会話で顧客対応を完結。
音声ツール利用メモリRAGDemo · hover to play
See more alternatives: alternatives to Retell AI · alternatives to Synthflow
Want the real monthly cost at your volume? Run the TCO calculator →
← Build your own comparison