SB Intuitions, the SoftBank Group Corp affiliate focused on Japanese large language models, opened a free public beta of its Sarashina service on Tuesday, exposing six models for chat, search, safety screening and Japanese–English translation through a browser and an application programming interface.
What Sarashina offers
Users can sign in with a Google account without a prior application, according to materials published with the launch. The browser experience targets conversational tests, while developers can wire the same endpoints into prototypes via API keys subject to rate limits.
SB Intuitions has not set an end date for the free tier, leaving commercial pricing and enterprise contracts for a later announcement.
Model lineup
The six-model bundle separates general dialogue from retrieval-oriented search, a safety classifier, translation and smaller variants tuned for latency. That split lets product teams call a lightweight guardrail model before serving user-facing answers—a pattern enterprise buyers increasingly demand after public chatbots hallucinated policy numbers.
SoftBank’s parent company has been rebuilding AI credibility after operational headaches elsewhere in its portfolio; Sarashina is as much a developer-relations play as a consumer chat site.
Data and privacy
Documentation states beta traffic may be used to improve model quality, a standard trade-off that privacy officers will scrutinize. Corporate testers are advised to avoid pasting customer records into the public endpoint until enterprise terms land.
Japan’s Personal Information Protection Commission has been active on AI training data this year; SB Intuitions emphasizes domestic hosting and Japanese-language prioritization in marketing copy.
Competitive field
NTT Corp, Fujitsu Ltd and startups such as Elyza Co. already ship Japanese LLMs to government pilots. Sarashina’s advantage is SoftBank’s enterprise salesforce and cloud bundles, not a unique architecture reveal on day one.
Open-weight models from overseas still tempt cost-sensitive developers; SB Intuitions must show accuracy on keigo, legal Japanese and technical manuals to win ministry RFPs.
Enterprise path
Telecom and bank innovation labs in Tokyo said they will benchmark Sarashina against internal fine-tunes of global models. Latency from inference regions inside Japan will matter for call-center copilots regulated to keep data onshore.
Partnerships with CEATEC exhibitors this week could produce reference architectures by year-end.
Risks
Free betas can become expensive if GPU clusters fill with abuse traffic; rate limits are the first defense. SoftBank investors will also watch whether Sarashina diverts capex from the chip investments that weighed on the parent’s equity story this week.
Bottom line
Sarashina’s public beta puts SoftBank’s Japanese-language model family in developers’ hands ahead of paid enterprise tiers, testing whether domestic accuracy and API access can compete with global LLMs in Japan’s regulated industries.