Nittei-san

Nittei-san is a web-based scheduling tool. An organizer creates a calendar, enters possible time slots, adds expected members, and shares the URL. Participants open the link, select their name, and mark their preferred dates and times, with changes shown in real time to everyone accessing the link. The page states it can be used for free indefinitely and requires no account registration, login, or download. Users can log in with Google to load their own calendar events, which appear faintly on the shared calendar. Available time slots can be copied to the clipboard as text for notifying others. The page explicitly states it has no notification or reminder features, does not register email addresses, and does not automatically add finalized dates to users' calendars.

Key features

• Shareable calendar URL that anyone can access without registration or login
• Real-time simultaneous editing by everyone accessing the shared link
• Organizer can create a new scheduling calendar and enter possible time slots
• Organizer can add expected members in advance; participants can add themselves
• Participant selects their name and marks preferred dates and times
• Optional Google login to load and view the user's own calendar events on the shared calendar
• Copy available time slots and member availability to the clipboard as text
• Batch register members via paste
• Paste and set candidate dates in free-text format
• Start a new scheduling session and clear time slots
• Mobile usability improvements and full-screen view

Best suited for

• Scheduling meetings with teams or external partners without requiring account setup
• Coordinating events and appointments among groups
• Quick schedule adjustments with participants who do not use the same calendar tools

Pricing

Free indefinitely, according to the page; no paid tiers are described.