Overview
Synthflow is a no-code Voice AI platform for building, testing, and deploying AI phone-call agents (both inbound and outbound). Key capabilities include a no-code Flow Designer with subflows, Voice API, transcription via Deepgram, GPT-4o-based LLMs with an option for customers to use their own OpenAI key, voicemail detection, sentiment analysis, human handoff, testing & versioning (Test Center), analytics, webhooks, and developer resources such as API references and custom actions. Synthflow operates its own telephony network with SIP trunking and carrier integration to reduce vendor lock-in and optimize latency. Pricing is consumption-based with workflow units ($0.002 per workflow), concurrency units ($7 per concurrent call), per-minute rates roughly $0.12–$0.13/min on standard plans and down to ~$0.08/min on enterprise/volume deals, and phone numbers at $1.50/month. Plans include Pro, Growth, Agency, and Enterprise with included minutes/packages and volume discounts; a 14-day free trial is offered. Integrations include HubSpot, Google Cloud, Zapier, RingCentral, Cisco/Avaya/Genesys, Deepgram, OpenAI (bring-your-own-key), Stripe, and Salesforce; Synthflow advertises 200+ tool integrations and a partner/certified solutions partner program. Security and compliance mentions include end-to-end encryption, HIPAA/GDPR readiness, regional deployments, governance and audit logs, and enterprise SLAs (99.9% referenced in news materials and SLA options for Enterprise). News/traction: reported Seed round (2024) $7.4M and Series A (2025) $20M led by Accel (total $30M), founders Albert Astabatsyan, Hakob Astabatsyan, and Sassun Mirzakhan-Saky; press materials reference millions of hours saved, tens of millions of calls handled, G2 recognition, and ~1,000+ customers in press. Legal/operating entity: AgentFlow AI GmbH (Kurfürstendamm 15, 10719 Berlin); representatives: Hakob Astabatsyan, Albert Astabatsyan, Sassun Mirzakhan-Saky; Charlottenburg HRB 255004 B; VAT DE363380350; [email protected].
Key Features
No-code Flow Designer
Visual flow builder with subflows for designing call agents without code.
Voice API & Telephony
Own telephony network, SIP trunking and carrier integrations to avoid vendor lock-in.
Transcription & LLMs
Transcription via Deepgram and GPT-4o-based LLMs with option to use customer's OpenAI key.
Testing & Versioning (Test Center)
Simulated call testing, accuracy/compliance checks, versioning, rollback and pre-deploy tests.
Monitoring & Analytics
Analytics, sentiment analysis, voicemail detection, and governance/audit logs for enterprise use.
Integrations & Partner Ecosystem
200+ integrations including CRM, CCaaS and automation tools; certified solutions partners and marketplace approach.
Who Can Use This Tool?
- Contact centers:Automating support, appointment booking, lead qualification and call handling at scale.
- Enterprises:Enterprise-grade telephony, SLA-backed deployments, advanced security and integrations.
- BPOs / Agencies:Multi-tenant/white-label solutions, agency billing and templates for resellers and partners.
- SMBs:Template-driven flows and self-serve onboarding for smaller teams and simple automation.
Pricing Plans
For small teams; basic included minutes and core features.
- ✓Approx. ~2,000 included minutes
- ✓~8,000 workflows (typical limit referenced)
- ✓~25 concurrent calls (typical limit referenced)
- ✓No-code workflow builder, team access
- ✓Basic support (ticket-based), test & staging
- ✓Self-serve onboarding and standard integrations
For scaling teams; expanded limits and billing controls.
- ✓Approx. ~4,000 included minutes
- ✓~42,000 workflows (typical limit referenced)
- ✓~50 concurrent calls (typical limit referenced)
- ✓Up to ~25 subaccounts
- ✓Rebilling / billing controls, expanded integrations
- ✓Faster onboarding options
For agencies and resellers; multi-tenant and white-label capabilities.
- ✓Approx. ~6,000 included minutes
- ✓~100,000 workflows (typical limit referenced)
- ✓~80 concurrent calls (typical limit referenced)
- ✓Unlimited subaccounts, white-labeling
- ✓Multi-tenant features, agency-focused billing & templates
- ✓30-day onboarding
Custom volume and features with dedicated support and SLAs.
- ✓Custom included minutes and concurrency (tailored pricing)
- ✓SIP trunking and guaranteed SLA/uptime
- ✓Dedicated solution architect and enterprise-level support
- ✓White-glove onboarding and advanced security/compliance (HIPAA/GDPR)
- ✓Volume per-minute discounts (can reach ~ $0.08/min)
14-day free trial to build flows and test live calls.
- ✓14-day access to build flows and test live calls
- ✓Intended for evaluation before committing to a paid plan
Pros & Cons
✓ Pros
- ✓No-code flow designer enables building phone-call agents without coding
- ✓Built-in telephony network with SIP trunking to reduce vendor lock-in and lower latency
- ✓Wide integration ecosystem (200+ integrations) and partner program
- ✓Testing, versioning, and analytics tools (Test Center) for pre-deploy validation
- ✓Enterprise security and compliance mentions (HIPAA/GDPR readiness, encryption)
✗ Cons
- ✗The /features path returned a 404 during collection
- ✗Automated extraction of full pricing plan feature lists failed validation due to long lists on the site (detailed raw lists were not included here)
Compare with Alternatives
| Feature | Synthflow | Pearl (by NLPearl) | Retell AI |
|---|---|---|---|
| Pricing | N/A | $100/month | N/A |
| Rating | 8.0/10 | 8.0/10 | 8.1/10 |
| No-code Flow | Yes | Yes | Yes |
| SIP & Telephony | Yes | Yes | Yes |
| Testing & Simulation | Yes | No | Yes |
| LLM & TTS | Yes | Partial | Yes |
| Monitoring & Analytics | Yes | Yes | Yes |
| Compliance Controls | Yes | No | Yes |
| Developer Extensibility | Yes | Yes | Yes |
| Scale & Concurrency | Yes | No | Yes |
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