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Retell AI vs Synthesia: 2026 comparison

Production voice agent platform — LLM-native phone agents with low-latency streaming and per-minute pricing.

🎧SupportAutonomousPay per task
VoiceTool useMemory

AI video studio — turns scripts into polished talking-head videos with avatars in 140+ languages.

📣MarketingAssistantSubscription · from $22
VisionVoiceTool use

Retell AI vs Synthesia — specs

SpecRetell AISynthesia
Agent Rank72 / 100 (A)70 / 100 (B)
AutonomyAutonomousAssistant
PricingPay per task · Free tierSubscription · from $22
Open sourceNoNo
CapabilitiesVoice, Tool use, MemoryVision, Voice, Tool use
Integrations3 apps4 apps
VerifiedVerifiedVerified
ReleasedMar 2025Jan 2025

Categories: Retell AISupport · SynthesiaMarketing

Agent Rank breakdown

Retell AI
Agent Rank
72/ 100
AA-tier
Autonomy fit
9
Capabilities
6
Integrations
4
Pricing value
9
Polish & maturity
5
Verifiability
10

Auto-computed from autonomy, capabilities, integrations, pricing, maturity and editorial verification. Updated every deploy. How is this computed?

Synthesia
Agent Rank
70/ 100
BB-tier
Autonomy fit
7
Capabilities
6
Integrations
4
Pricing value
8
Polish & maturity
7
Verifiability
10

Auto-computed from autonomy, capabilities, integrations, pricing, maturity and editorial verification. Updated every deploy. How is this computed?

Pros & cons

Retell AI
Pros
  • +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
Cons
  • 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
Synthesia
Pros
  • +Studio-quality avatar video — the most polished output in the category
  • +140+ languages with native-quality lip-sync
  • +Custom avatar creation with explicit consent flow
Cons
  • Pricier per minute than HeyGen for similar output
  • Best for B2B training and marketing — less consumer-friendly
  • Minute caps come into play quickly on the Starter tier

Pricing

Retell AI
Pay-as-you-go
Free
Developers
  • +~$0.07/min
  • +Production-ready API
Recommended
Scale
Custom
High-volume voice ops
  • +Volume discounts
  • +Dedicated infrastructure
  • +Custom models
Synthesia
Starter
$22/mo
Individuals
  • +10 min/mo
  • +125+ avatars
  • +140+ languages
Recommended
Creator
$67/mo
Solo creators
  • +30 min/mo
  • +Voice cloning
  • +Personal avatar
Enterprise
Custom
Large teams
  • +Custom volumes
  • +Custom avatar production
  • +API access
  • +SSO

Which one should you pick?

Retell AI

Pick Retell AI if cost is the main constraint or if you want the highest autonomy and the verification loop is in place.

Try Retell AI →
Synthesia

Pick Synthesia if its specific capabilities (Vision, Voice) match what you need.

Try Synthesia →

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Frequently asked

Should I pick Retell AI or Synthesia in 2026?+

Pick Retell AI if cost is the main constraint or if you want the highest autonomy and the verification loop is in place. Pick Synthesia if its specific capabilities (Vision, Voice) match what you need. Most working teams running both can use Retell AI for primary work and Synthesia for the workflows where its specific strengths matter.

What's the price difference between Retell AI and Synthesia?+

Retell AI starts at Pay per task · Free tier; Synthesia starts at Subscription · from $22. 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 Synthesia?+

Retell AI is the more autonomous of the two (Autonomous vs Assistant). Higher autonomy ships throughput faster but requires verification loops in place — see our autonomous-vs-copilot framing for when each tier wins.

Want the real monthly cost at your volume? Run the TCO calculator →
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