Kotoba Technologies, headquartered in Tokyo (with a Seattle presence), develops Japanese-centric large language models and speech AI for real-time simultaneous interpretation, speech-to-speech translation and transcription. The company's roots trace to a project building a Japanese LLM on the Fugaku supercomputer. It has shipped Kotoba SpeechGen and the DOTSU iOS app, which performs live speech-to-speech translation with transcription. In June 2025 Kotoba closed a second seed round of $11.83 million (≈¥1.7 billion), bringing total seed funding to about $13.33 million. The round was led by Globis Capital Partners and Boost Capital, with SIP Capital and angels including Joi Ito (co-founder of Digital Garage) and Thomas Wolf (co-founder and CSO of Hugging Face) participating, to accelerate commercialization of its interpretation technology.
Kotoba Technologies
ActiveReal-time AI simultaneous speech translation and interpretation
Total raised
$11.8M
1 round
Stage
Seed
Jun 2025
Team
11-50
since 2023
Pricing
Freemium
free plan
Founded
2023
Tokyo, Japan
Agent-ready
API
Score 40/100
Real-time simultaneous interpretation
Speech-to-speech translation
Japanese-centric speech LLM
Kotoba SpeechGen voice generation
DOTSU iOS translation app
Live transcription
Built on Fugaku supercomputer research
Multilingual speech support
40/100
Developing
MCP server
Public API
Webhooks
OAuth 2.0
SDKs
Jun 2025 Seed $11.8M ● Globis Capital Partners
Capital network
$13.3M raised ·5 backers·8 network links
- Backers5
- Shared portfoliocompanies these backers also fund
- Extended networkfunds that co-invest alongside them
Wispr
Effortless voice dictation powered by AI
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ElevenLabs
The most realistic AI voices for creators, developers, and enterprise.
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Wondercraft
The Canva of audio — generative AI podcasts and ads
AI VideoAI Voice & Speech
David AI
The data layer for next-generation audio and voice AI models
AI Voice & SpeechAI Audio
Assort Health
AI Voice & Speech
Regal AI
AI Voice & Speech
- What does Kotoba Technologies build?
- Japanese-centric speech LLMs powering real-time AI simultaneous interpretation, speech translation and transcription.
- Where is Kotoba based?
- Tokyo, Japan, with a presence in Seattle.
- How much has Kotoba raised?
- About $13.33M in seed funding, including an $11.83M second seed in June 2025 led by Globis Capital Partners.
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