WhenTo

Free plan Self-hostedWeb

What WhenTo is

WhenTo is a free web application for organizing recurring events with collaborative calendars based on participant availability. People can define weekly availability patterns and add exceptions for special weeks. Calendar owners set the minimum number of participants needed to confirm an event, and notifications for reaching that threshold can go through email, Discord, Slack, or Telegram. Participants respond through a shared link without creating accounts. The maker describes WhenTo for RPG and board game groups, amateur sports, music bands, and team meetings. It is available as a hosted cloud service or as self-hosted software. Cloud accounts allow three calendars per account, while self-hosting allows unlimited calendars; the maker says there is no paid tier or way to raise the cloud limit. Docker Compose deployment instructions are provided, and self-hosted data stays on the operator’s infrastructure. Security details include RS256 JWT authentication, bcrypt password hashing, rate limiting, regenerable public and iCalendar tokens, and HSTS, CSP, and X-Frame-Options headers. Calendar synchronization is one-way, and no mobile apps are listed.

Who it suits

WhenTo suits groups coordinating recurring activities, including games, amateur sports, bands, and team meetings. It also fits operators who want self-hosting and participants who should respond without accounts.

What it does well

Weekly availability patterns and exceptions
Threshold notifications through four channels
Shared-link participation without accounts
Unlimited calendars when self-hosted
Docker Compose deployment instructions

What to know first

Cloud accounts are limited to three calendars
No paid tier to raise the cloud limit
Calendar synchronization is one-way
No mobile apps listed

Plans

Plan	Billed and limits	Price
Self-hosted	Unlimited calendars	Free
Cloud	3 calendars per account	Free

As whento.be lists them, read 12 Oct 2026. The maker's own page has the final word.

Verdict

WhenTo focuses on recurring scheduling around shared availability rather than one-off polls. Its free cloud option is capped at three calendars, while self-hosting removes that calendar limit but requires operating the software yourself.

Facts from WhenTo's own pages

Calendar sync: An iCalendar subscription feed syncs qualifying events with Google Calendar, Apple Calendar, Outlook, and Thunderbird. · github.com, 12 Oct 2026
Cloud limit: Cloud accounts are limited to three calendars, and the repository says there is no paid tier or way to raise the limit. · github.com, 12 Oct 2026
Event threshold: Calendar owners can set a minimum participant threshold for confirming an event. · github.com, 12 Oct 2026
Free plan: Yes · github.com, 22 Sept 2026
License: The repository says WhenTo is licensed under Business Source License 1.1 and converts to Apache 2.0 on 2035-12-03. · github.com, 12 Oct 2026
Mobile apps: none · github.com, 22 Sept 2026
Notifications: Threshold notifications are available through email, Discord, Slack, or Telegram. · whento.be, 12 Oct 2026
Participant access: Participants can indicate availability using a shared link without creating accounts. · github.com, 12 Oct 2026
Purpose: WhenTo is a web application for organizing recurring events through collaborative calendars where participants share their availability. · github.com, 12 Oct 2026
Recurring availability: Participants can set weekly availability patterns and exceptions for special weeks. · github.com, 12 Oct 2026
Scheduling links: Yes · github.com, 22 Sept 2026
Security: The repository describes RS256 JWT authentication, bcrypt password hashing, rate limiting, regenerable public and iCalendar tokens, and HSTS, CSP, and X-Frame-Options headers. · github.com, 12 Oct 2026
Self-hosting: The maker provides Docker Compose deployment instructions and says self-hosted data stays on the operator's infrastructure. · github.com, 12 Oct 2026
Shared calendars: Yes · github.com, 22 Sept 2026
Support: The maker lists GitHub Discussions for community support and GitHub Issues for bug reports. · github.com, 12 Oct 2026
Use cases: The maker describes use for RPG and board game groups, amateur sports, music bands, and team meetings. · github.com, 12 Oct 2026

Where WhenTo stands on Freedom251

Calendar apps#87 of 194