Kotoba Technologies announced that it raised an additional $10 million in seed funding to expand its real-time voice AI platform across East Asia.
The round was led by Kindred Ventures, with participation from Salesforce Ventures and Sony Innovation Fund. The financing brings Kotoba’s total funding to $23 million.
Kotoba develops real-time speech models optimized for East Asian languages. Its proprietary model, Koto, is built for real-time speech applications including AI agents, smart hardware devices, and simultaneous speech translation.
Koto is designed to deliver strong performance in Japanese, Korean, and Chinese. The model can be deployed as speech-to-speech models, as well as ultra-low-latency speech-to-text and text-to-speech models.
The company’s technology can be deployed in data centers and on-device, including smartphones and wearables. Koto is already running on-device with enterprise customers in Asia and the United States.
Kotoba plans to use the new funding across three main priorities: advancing speech-to-speech models, expanding on-device deployment, and accelerating agentic rollout for enterprise customers.
For speech-to-speech, Koto has demonstrated sub-2-second latency in simultaneous translation. Kotoba plans to invest further in this model family and extend it into broader use cases such as AI agents and smart devices.
For on-device deployment, the company will focus on running Koto efficiently on edge chips and exploring wider distribution across automobiles, electronics, and AI wearables through partnerships.
For enterprise use cases, Kotoba plans to improve the Koto ecosystem for customers globally and support companies expanding into Asian markets. This includes continued model ecosystem development and forward-deployment efforts.
Kotoba has also released an alpha version of its API and an easy-to-use Python SDK to broaden developer access. Its speech-to-speech simultaneous translation models, speech-to-text models, and text-to-speech models are now available through the API, while on-device models can also be tested through the API and SDK.
Koto is already in production with global organizations, including Fortune Global 500 companies and AI-native startups. The technology is used for AI voice agents, contact center voice interfaces, wearable devices, and AI-powered simultaneous translation.
Kotoba’s proprietary app, Kotoba, is also seeing growth across East Asia. The app provides simultaneous translation, note-taking, and AI summaries across 21 languages and has surpassed 180,000 users.
The company was founded in 2023 by Cornell and University of Washington PhDs Noriyuki Kojima and Jungo Kasai. Kotoba is headquartered in San Francisco and has a Japan office in Tokyo.
KEY QUOTES:
“Asia is home to nearly 5 billion people, and to start, East Asian countries represent 1.6B of that continental population. Roughly half of the world’s knowledge workers speak an Asian language as their first native tongue. The complexities of getting the unique aspects of Asian languages requires a unique training strategy and learning loop approach with a deep understanding of each language and market.”
“The Kotoba research team brings extreme focus and depth to developing the world’s fastest and most genuine speech models for both high-controllability pipelines for agents, or incredibly fast and accurate native speech-to-speech models for realtime communication and translation. On both recognition and synthesis, their Koto family of models – TTS, STT, and Speech-to-Speech – models performed better than existing models developed by American and European research labs. We’re thrilled to support Kotoba’s mission to bring state-of-the-art speech models, multimodal agents, voice-centric wearables, physical AI hardware, and the holy grail of realtime translation to the entire world.”
Steve Jang, Founder and Managing Partner of Kindred Ventures
“Under a co-founding team that combines exceptional research capabilities with strong business execution, Kotoba Technologies is developing world-class voice AI and steadily advancing its real-world implementation. In addition to their high technical capabilities, we see immense potential in their focus on driving implementation in business environments. We look forward to leveraging Salesforce’s global network and expertise to support the company’s further business growth.”
Ken Asada, Partner, and Sho Yamanaka, Principal at Salesforce Ventures
“Real-time voice communication remains one of the most technically challenging AI frontiers. Kotoba has demonstrated impressive real-world results in both translation quality and latency, outperforming many existing approaches in speech-to-speech translation. With encouraging early product-market fit and growing adoption among enterprise customers, Kotoba is building more than a translation application, it is creating a voice AI infrastructure platform with potential applications across enterprise, telecom, electronics, and consumer markets.”
Austin Noronha, Managing Director of Sony Ventures-US
