Top 13 Synthflow Alternatives and Competitors in 2025

AI voice automation is rapidly growing, with the global market expected to rise from $3.14B in 2024 to $47.5B by 2034 at a 34.8% CAGR, driven mainly by enterprise adoption in banking, healthcare, and retail. On Trustpilot, the platform scores 4.5/5 with users praising its intuitive, easy-to-use design for managing AI voice agents, while some customers complain "Customer support is a complete JOKE!".

Synthflow is SOC2, HIPAA, and GDPR-compliant, fully meeting US and EU data regulations. It delivers a human-like voice with <500ms latency for fast, clear, and reliable multilingual conversations. Voice agents are available in 30+ languages. Pricing starts at $29/month for 50 minutes with enterprise calls from $0.08/min, plus a 14-day free trial.

Some Reddit users note, “Synthflow rates aren’t accurate….”. In this blog, we break down Synthflow AI’s key drawbacks and highlight more affordable, scalable alternatives for building superior voice AI solutions.

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List of Alternatives

1. Dograh AI
2. Retell AI
3. Vapi AI
4. Bland AI
5. Hamming AI
6. Dialogflow
7. Poly AI
8. Goodcall
9. Voiceflow
10. Lindy
11. Smallest AI
12. Botpress
13. Dasha AI

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Best Synthflow Alternative Recommendation

If you’re looking to automate conversational workflows or need a Synthflow alternative, here are 13 top AI agent platforms reviewed by features, pros, ideal users, challenges, and pricing.

1. Dograh AI

Dograh stands out as a powerful open source alternative to Voiceflow with several advantages :

• Free Open Source - Dograh is an free open source voice ai platform giving full flexibility to developers to customize, self host and extend features. Users should be able to try out in 1 line (should take <2mins ideally).
• 2 Min Launch - In the Create Workflow Dashboard, you can launch a voice agent in just 2 minutes by selecting inbound or outbound calls and writing “For the use cases of…” to describe your agent (e.g., qualify real estate leads, screen candidates, or handle customer support). This description becomes the LLM prompt, instantly generating your customized workflow.
• Pre Built Template - Dograh’s Pre-Built Templates let you launch an AI voice agent in just 2 minutes without writing any code or prompts, with easy customization through a global node for user-specific preferences.
• Global Node - The global node enables users to tailor their voice agents with specific preferences, such as updating industry names or applying custom modifications for personalization.
• License - Dograh AI is released under the BSD 2-Clause License, the same license as its foundational projects, ensuring full compatibility and the freedom to use, modify, and distribute.
• Easy to Use and Dependability - With AI to AI testing (over calls) and feedback loop through call summary, it is fairly easy to build extremely dependable bots with Dograh AI. Also this helps cut down on time needed to build the voice agent, and significantly improves time to market.
• LoopTalk - Think AI calling AI. Dograh’s LoopTalk auto-tests voice bots using AI-driven customer personas to simulate real-world scenarios boosting accuracy and letting you get started in minutes.
• No Double Billing - Dograh offers transparent pricing with no double billing charges for STT, TTS and LLM. And the open source solution is free to host and use.
• End-to-End Support - Dograh’s professional team offers end-to-end support from integration and workflow setup to analytics and optimization.
• Faster Setup - Dograh offers drag and drop workflow builder UI and prebuilt workflow as per your business needs.

Key Features

• NEPQ led Sales - Uses Neuro-Emotional Persuasion Questioning (NEPQ) to drive deeper engagement and guide conversations effectively.
• Real-Time Response - Dograh enables low-latency (<500ms), human-like voice conversations for seamless user interactions.
• Longer Conversation - Dograh multi-agent bots can handle calls up to 45 minutes, maintain full context throughout conversations without hallucinations.
• Human Like Speech - Pauses, Filler words & clear tone for realistic, engaging voice interactions.
• Emotionally Effective - Understand user concerns by actively empathizing and probing their pain points to deliver more personalized, effective voice interactions.
• Tailor-Made Build - Dograh experienced team offers hands-on support to help you design and deploy custom voice agents tailored to your scripts and business needs.
• Multilingual Voice Support - Support multilingual voice agents using top STT and TTS providers, enabling natural and fluent conversations for diverse global audiences.
• Expert Cloud Support - Get expert cloud support with Dograh test and refine your voice agent in real time using our intuitive, cloud-hosted interface.
• Flexible Deployment Option - Dograh supports both cloud and open-source deployments, giving you flexibility based on your business and technical needs.
• Customer Support - Dograh’s dedicated support team ensures your Voice AI runs smoothly from setup to ongoing updates with fast, reliable assistance.
• Data Privacy - Your data privacy is our top priority. Dograh’s open source solution helps adhere to strict GDPR and HIPAA standards to keep your information secure and fully compliant.

Ideal Users

• Real Estate Agent
• Customer Support
• Sales and Marketing Automation
• Tech Support
• Finance, Insurance and Banking
• E-Commerce
• Healthcare
• Logistics & Home Services
• Travel & Hospitality

Pricing

Dograh offers an open-source solution with no platform fees, making it highly cost-effective, customizable, and scalable. In contrast, Synthflow’s Starter plan costs $29/month for 50 call minutes and enterprise grade calls start at $0.08/min.

Quick Comparison Table

2. Retell AI

Retell AI was launched on February 8 2022, Retell AI developed production ready ai voice agent for automating and scaling phone conversations across industries like healthcare, logistics and finance. But just like Synthflow, Retell is still based on old technology and best suited for smaller use cases.

Key Features :

• Retell is SOC 2 Type 1 & 2, HIPAA, and GDPR compliant, meeting all industry compliance standards.
• Natural, smooth, and empathetic AI conversations with only 500ms latency.
• Support 18+ languages, and can dial to any country's phone numbers.
• Effortlessly handle millions of calls with scalable concurrent calling.
• Offer average 99.99% uptime and effortless fallback. Retell AI ensures your agents are always production-ready.
• Provide native and external connectivity to any CRM, telephony, automation platform, and database.

3. Vapi AI

Vapi the voice ai platform founded in 2020 by Jordan Dearsley and Nikhil Gupta, Vapi is a voice AI platform offering highly flexible, developer-focused toolsets to help businesses build, deploy and scale AI-driven voice interactions and phone agents with ease. With sub-500 ms latency and enterprise-grade security, it supports HIPAA, SOC 2, and GDPR compliance.

Key Features :

• Sub 500 ms latency
• Easy integration and light weight code
• Full AI powered pipeline (TTS/STT, LLM)
• Security and Compliance HIPAA, SOC2, GDPR compliance for enterprise-grade security
• Conversation Orchestration and Custom Flows
• 100+ languages supported out-of-the-box, strong for global use
• Analytics dashboards with real-time and historical KPI tracking

4. Bland AI

Bland AI was launched in 2023, the company focuses on offering conversational AI platforms for automating phone calls. Bland AI is looking to revolutionize phone communication with scalable, secure and highly customizable AI agents for customer support, sales and operations.

Key Features :

• Ultra Realistic AI Phone Calls - Human Like
• Self Hosted End-to-End Infrastructure
• Expert Implementation
• Data in House to store and manage data
• SOC2 Type II Complaint for Security
• GDPR / HIPPA Complaint
• Real Time Analytics and 99.9% Uptime
• Pricing $ 0.09 / Minute (Without Hidden Charges)

Vapi AI vs Dograh AI : Which is Best For You in 2025?

Businesses are turning to voice assistants for 24/7 support and faster issue resolution. This blog compares Dograh AI and Vapi AI covering features, performance, integrations and pricing, to help you choose the right voice automation platform for your business needs.

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5. Hamming AI

Hamming AI can scale, test and monitor AI voice agents seamlessly, from simulating thousands of calls before launch to auditing every live conversation in production. Always-on heartbeat checks catch regressions instantly, while real-world scenarios help optimize performance with actionable, AI-powered insights. The platform auto-generates diverse caller personas, including edge cases, to ensure every branch of your voice agents is tested. Simply connect your voice infrastructure, run automated tests, and start seeing insights within minutes.

Key Features :

• Real-time call analytics score every call within seconds to spot metric slips.
• 24/7 heartbeat checks with alerts for instant regression detection.
• Multilingual AI voice agents (English, French, German, Hindi, Spanish, Italian, etc.).
• Seamless integration: dial via SIP or connect directly to LiveKit/Pipecat; one-click imports from Hopper, Retell, VAPI.
• Convert live conversations into replayable test cases (audio, transcript, intent) in one click.
• Auto-generate test cases and evaluate performance, no manual setup needed.
• Edge-case and stress testing built-in.

6. Dialogflow

Dialogflow, Google’s conversational AI agent, delivers personalized self-service and natural, human-like voice experiences for highly engaging customer interactions. Powered by Google’s leading generative AI, it enables rich, intuitive conversations while ensuring predictable and safe performance through deterministic controls. It serves as a comprehensive development platform for creating both text and voice-based virtual agents.

Key Features :

• Powered by leading Generative AI
• Human like multilingual conversations
• Easily build AI agents with no code
• Personalized customer interaction
• Integrate with your own CRM and data sources
• Multimodal interaction with voice, text or images
• Out-of-the-box connectors 30+ data retrieval connectors and 70+ action connectors to allow your agent to take actions

7. Poly AI

Poly AI was founded in 2017, focuses on building natural sounding conversational AI solutions. It is extensively used in customer service environments like telecoms, hotels, banks and e-commerce.

Key Features :

• Multilingual Support 12 languages.
• Scalable and 24 / 7 support.
• Immediate response to calls to maintain customer trust.
• Provide actionable insights from real conversations.
• Seamless integration with ( AVAYA, BT etc ).
• ISO 27001-certified, GDPR, HIPPA and SOC2 Type II Security.

8. Goodcall

Goodcall AI was originally incubated in Google Area 120 under the name CallJoy and evolved into Goodcall. It is a cutting edge phone assistant that leverages the power of Chat GPT to provide seamless communication. Focuses on ethical AI usage, transparency, consent in calls, and calls human assistance when needed.

Key Features :

• 97% caller interaction rate.
• Provide easy to use interface with full control over workflows.
• HIPAA Compliant Phone AI Agents.
• Integration with Google cloud AI.
• Ethics focused AI usage.
• AI phone agents and virtual receptionist for local businesses.

9. Voice Flow

Voiceflow was founded in 2019, the company provides a platform for building conversational voice ai agents. Voiceflow is a no code platform for designing, prototyping and deploying AI chatbots and AI assistants. It allows users to build complex workflows with custom code.

Key Features :

• No Code and Collaborative Builder.
• Design, test and deploy AI-powered voice agents that are fast, human-like, and scalable.
• Build Chat Agents with deep capabilities and interface customization.
• Supports integration with existing tech stacks.
• Over 250,000 users and teams worldwide.
• Provides APIs, workflow versioning, commenting, and real-time collaboration.

10. Lindy AI

Lindy was founded in 2023 and launched in 2024, is a no code platform that allows users to create and deploy AI powered automations. Lindy offers a mission to empower the future of work by giving every team their own AI employees.

Key Features :

• Connect seamlessly with all your apps, from Gmail to HubSpot.
• Help in providing leads 200+ sources.
• Helps scale operations by offloading routine tasks to AI no extra hires needed.
• Seamlessly connects with over 1,600 applications.
• Supports sales, marketing, recruiting, support and admin teams.
• Saves time up-to 20 - 30 hours per week.

11. Smallest AI

Smallest AI was founded in 2023, the company quickly gained attention for its rapid innovation in high performance voice AI. Human-like voices and smart agents boost customer engagement, with an average call time of 130 seconds.

Key Features :

• Accurate handling of complex cases enables better automation with just 5% human fallbacks.
• Auto-dialers and verified numbers drive 80% call connectivity rate.
• Telephony Analytics Integration.
• Electron SLM, in house model trained on millions of conversation.
• Use Cases in Customer Support, Debt Collector, Interview Screening and Real Estate Agent.

12. Botpress

Botpress is a series of B companies based in Canada founded in 2016 by Sylvain Perron and Justin Watson. Botpress is an all-in-one platform for building AI agents powered by latest LLM’s. The platform provides the core infrastructure needed to build and run AI agents in production. Unlike rigid tool-calling systems, Botpress’s custom inference engine runs internally, handling complex logic, safe JavaScript execution and structured responses with no extra setup.

Key Features :

• Augment customer support workflows
• Connect to top tools and channels with ready-to-use integrations for smart workflow automation
• Integrate with existing systems
• Deliver contextual conversations
• Reduce call centres volume by 30%
• Able to reduce 65% of support tickets with 0 AI hallucinations
• Platform claim 98% resolution rate

13. Dasha AI

Deploy conversational voice AI agents with Dasha that sound human and help drive business growth. Dasha’s production-ready technology works from day one, delivering 99.99% uptime SLA. Dash AI Pricing includes 1,000 free minutes each month, then $0.08 per minute, with unlimited concurrent calls (up to 1,000 per AI agent or more). For support, reach out at support@dasha.ai or schedule an onboarding call to get started.

Key Features :

• Go live in 30+ languages, with bots that can switch mid-call for global support.
• Instantly scale from 10 to 1,000+ concurrent calls without quality loss.
• Move from prototype to full-scale deployment with production-ready voice apps.
• Seamlessly integrate with existing VoIP, numbers, and carriers.
• Designed for sales, support, and engagement automation.
• Reliable, human-like AI interactions for industries needing scale and trust.
• Smart call routing by intent, language, or complexity; auto-detect voicemails.
• Integrate with Salesforce, HubSpot, Zendesk, and hundreds of tools.
• Clone any voice in minutes, replicate your team’s tone or build unique brand voices.

What Should You Look For In Voiceflow Alternatives ?

1. Pricing transparency and cost control without hidden charges.
2. Ease of building a voice bot and Reliability of the bot.
3. Simple Setup with No-Code/Low-Code Options.
4. Clear Voice, Low Latency and Natural Speech.
5. Seamless integration and workflow automation.
6. Security, compliance and deployment option.
7. AI-Powered Insights and Optimization with Built-In Testing Tools (e.g., LoopTalk).

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Dograh AIDograh AI

What to Look for in a Modern Voice Orchestration Platform

Enhanced Usability and No-Code Setup

Modern AI voice platforms offer no-code/low-code visual builders, letting non-developers quickly design and deploy voice agents using drag-and-drop editors, templates, and guided setup, cutting time-to-market and dev effort. Dograh goes further by combining this ease of use with advanced AI-driven features for faster, production-ready deployments.

High-quality AI phone agents

A great AI voice platform delivers natural, low-latency (under 500ms) speech with realistic human-like tone, pauses, and emotional nuance. This is crucial for long, multi-turn conversations using NEPQ-led persuasion without losing context or drifting off-topic. Dograh is a strong alternative, offering production-ready voice AI optimized for both speed and conversational depth.

Transparent & Low Pricing

Transparent pricing is essential for businesses aiming to scale efficiently. Many modern AI voice platforms offer bundled pricing that includes STT, TTS, and LLM usage. This eliminates hidden costs and avoids double billing issues. Dograh follows the same model, providing clear, bundled pricing to make scaling predictable and cost-effective.

AI Cold Calling Real Estate Script & Best Practices | Boost Leads with Voice AI

AI cold calling is transforming real estate prospecting with scalable outreach, personalized conversations, and 24/7 engagement. Agents close more deals faster, with properties seeing a 22% sales boost. 97% of SMBs report higher revenue and better client engagement using AI voice agents.

Dograh AIDograh AI

How to Choose Between so many Voiceflow Alternatives ?

When selecting a voiceflow.com alternative, keep these key factors in mind, and Dograh standing out across multiple areas:

1. Open Source: Dograh offers cost savings, data control, and flexibility with open-source solutions.
2. Reliability: Building a reliable voice bot is not trivial and hence Built-In AI Testing and self improving bots can help reduce errors and also with faster time to market.
3. Budget: Choose a platform with transparent, all-in-one pricing. Dograh and Insighto.ai offer more cost-effective options compared to Vapi’s layered hidden fees.
4. Ease of Use: For non-technical teams, platforms like Dograh, Tabbly, and Voiceflow offer intuitive no-code, drag-and-drop builders to quickly launch voice agents.
5. Scalability: If you're aiming for high-volume use, Dograh and Dasha.ai deliver strong infrastructure support and uptime performance.
6. Integrations: Dograh, Tabbly, and Synthflow integrate smoothly with CRMs, ERPs, Slack and other business tools for streamlined automation.
7. Multilingual Support: Dograh and Dasha.ai offer robust language capabilities, making them ideal for teams serving a global audience.

The Ultimate Guide to AI Calling Implementation-by Dograh AI

AI Calling Implementation is transforming customer service by boosting agent speed, efficiency, and customer satisfaction. Dograh’s open-source workflow builder streamlines this process, making it easy and cost-effective for businesses.

Dograh AIDograh AI

Getting started with Dograh

Interested in leveraging Dograh for lead generation, cold calling or business automation ? Here’s a streamlined path to getting started, along with direct links to essential resources :

1. Dograh AI: Quick Start Demo

2. Run Docker Command

Download and Start Dograh first startup may take 2-3 mins to download all images

Docker

3. Quick Start Instructions

Step by step written guide to building and deploying your first voice AI Agent

• Open Dashboard: Launch http://localhost:3000 on your browser.
• Choose Call Type: Select Inbound or Outbound calling.
• Name Your Bot: Use a short two-word name (e.g., Lead Qualification).
• Describe Use Case: In 5–10 words (e.g., Screen insurance form submissions for purchase intent).
• Launch: Your bot is ready! Open the bot and click Web Call to talk to it.

4. Community & Support

Join Slack Community and discuss issue with Dograh experts :

Join Slack Community

5. Additional Resource

FAQ's