Amazon Lex vs SOVA
Amazon Lex
aws.amazon.comSOVA
sova.aiSide by side
| Figure | Amazon Lex | SOVA |
|---|---|---|
| Price from | $0.50/mo | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | Yes |
| Web | Yes | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | — | Yes |
| iOS | Yes | Yes |
| Android | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | — | Yes |
| Plans published | 7 | 3 |
| Spec score · Conversational AI Platforms | 9.1 (#1) | 8.3 (#14) |
| Spec score · Chatbot Builders | 9.1 (#7) | 8.6 (#50) |
| Spec score · Conversational Chatbots Software | 9.1 (#2) | 8.3 (#11) |
| Deployment channels | multichannel | multichannel |
| Free plan | No | Yes |
| Knowledge-base answers | Yes | The IDE knowledge base stores information used to prepare assistant responses during training and retraining. |
| Maker history | Amazon Web Services says it launched in 2006. | SOVA's about page says the team's artificial-intelligence work began in 1997. |
| Purpose | Amazon Lex builds conversational interfaces for applications using natural language voice or chat. | SOVA is an open-source ecosystem for building conversational AI, including virtual assistants, chatbots, speech tools, and neural-network software. |
Plans
Amazon Lex
- Text requestsFree
- Speech requestsFree
- Automated Chatbot Designer$0.50 a month
- AWS Free TierFree
- Speech requestFree
- Text requestFree
- Automated chatbot designer$0.50, paid once
In their own words
Amazon Lex
Amazon Lex lets application builders create conversational interfaces that respond to natural-language voice or chat input. It combines automatic speech recognition for voice with natural language understanding for voice and text interactions. Builders can use a visual flow builder and AI bot generation. The Automated Chatbot Designer analyzes conversation transcripts and proposes an initial design with intents and slot types; Test Workbench supports creating test sets and reviewing results. For FAQ responses, an intent can query an authorized knowledge source and foundation models from Amazon Bedrock. Bots can be deployed on mobile devices and chat services including Facebook Messenger, Slack, Kik, and Twilio SMS. AWS integrations include Lambda for backend logic, Cognito for authentication, Polly for text-to-speech, and Amazon Connect for contact centers. Lex is available for Android, iOS, web, and API use. Text and speech requests use pay-as-you-use pricing, with no upfront commitment or minimum fee in the listed examples. Automated Chatbot Designer training time is listed at $0.50 a month, with pricing described as per minute of training time. The AWS Free Tier is available for six months after account creation, with credits subject to stated eligibility and expiry terms.
SOVA
SOVA is a free, open-source ecosystem for building conversational AI, including virtual assistants, chatbots, speech tools, and neural-network software. SOVA IDE provides tools to develop, test, and release assistants, with a knowledge base, dialog processor, and team development features. Its dialog language supports rules, variables, external database queries, and modular dialogue structures. ChatKit is a React component set for chat widgets, with file sending, media, message editing, search, and channel selection. SOVA ASR converts recorded or live speech to text, while SOVA TTS generates audio from text. The maker says these speech tools run locally and are licensed under Apache 2.0 for academic and commercial development. SOVA lists 28,853 hours of labeled Russian and English audio under CC-BY 4.0. Products can run offline, in Azure or AWS, or locally using Docker. SOVA Mobile for iOS and Android supports text and voice messaging, multiple assistants, and conversation history. The maker also directs enterprise inquiries to Sales.