☀

Calendarium Solaris

A universal calendar — based on natural rhythms and the cyclical movement of the sun

"Everything you need to know to use the Calendarium Solaris — from navigating the calendar to managing appointments."

The Calendar

Navigating months

Use the ‹ Prev and Next › buttons to move through the year. Click ☀ Today to jump back to the current date. The mini-calendar in the left sidebar mirrors your current position and can also be used for quick navigation.

Selecting a day

Left-click any day to select it — it will be highlighted and the mini-calendar updates accordingly. Right-click a day to open the appointment popup for that day.

Outside Days

Days marked with an outside day bar at the bottom fall outside the standard week cycle. They carry no weekday designation. There are six types:

Equinox 0°
Day 1 of the year — the Northward Equinox. Start of the Solaris year.
Solstice 90°
Day 92 — the Northern Solstice. Between Tertisol and Quartisol.
Equinox 180°
Day 186 — within Septisol, after day 3.
Solstice 270°
Day 275 — within Decisol, after day 1.
Yearday
Day 365 — closes the year.
Intercalary Day
Day 366 — leap years only. Equivalent to 29 February.
Tip: You can make appointments on Outside Days just like any other day — right-click the day to open the popup.

Date Converter

The converter in the left sidebar (or below the calendar on mobile) converts dates in both directions. Select a Gregorian date and click Convert ☀ to find the Solaris equivalent — or enter a Solaris date and click Convert 🌍 for the Gregorian date. The calendar will jump to the converted date automatically.

Note: 29 February always maps to the Intercalary Day of the corresponding Solaris year. The Gregorian coupling is fixed: Primisol 1 is always 21 March, regardless of Gregorian leap years.

Appointments

Appointments require a free account. Once logged in, right-click any day to open the appointment popup.

Adding an appointment

Fill in the title, choose whether it is an all-day event or specify a time, select a calendar, and optionally add notes. Click + Add to save.

Repeating appointments

Daily
Repeats every day.
Weekly
Repeats every 5 days (one Solaris week).
Monthly
Repeats every 30 days (one Solaris month).
Quarterly
Repeats every 91 days (one Solaris quarter).
Yearly
Repeats on the same Solaris date each year, accounting for leap years.
🎁 Birthday
Like yearly, but displays a gift icon and the person's age. Enter the birth year to calculate age automatically.
Custom period
Repeats every N days of your choosing (e.g. every 7 or 28 days).

Editing and deleting

Open the popup for a day to see its appointments. Each appointment has an ✎ edit button and an ✕ delete button. When deleting a repeating appointment you will be asked whether to remove only this occurrence or the entire series.

Privacy: All appointments are stored locally on your device only — nothing is sent to any server. Export your appointments as a .ics file to back them up or share them with other calendar applications.

Calendars

Logged-in users can create multiple calendars (agendas), each with its own name and colour. Appointments are assigned to a calendar when created. To manage your calendars, use the Calendars section in the left sidebar.

New calendar
Click + next to "Calendars", enter a name, choose a colour, and click Save.
Edit calendar
Hover over a calendar and click ✎ to rename it or change its colour.
Delete calendar
Hover and click ✕. This also removes all appointments belonging to that calendar.

Import & Export

Export

Click ⬇ Export .ics in the right sidebar (or at the bottom of the calendar on mobile) to download all your appointments as a standard .ics calendar file. Each appointment includes the Solaris date and a link to solariscalendar.org in its description.

Import

Click ⬆ Import .ics to import appointments from any standard .ics file (Google Calendar, Apple Calendar, Proton Calendar, etc.). A new calendar is automatically created with the filename as its name, and all imported appointments are placed in it. Duplicate appointments (identified by UID) are skipped.

Tip: Use export and import to transfer your appointments between devices, as appointments are stored locally and not synchronised automatically.

Upcoming

The Upcoming panel in the right sidebar shows your next appointments, grouped by month, for up to three months ahead. Click any appointment to jump directly to that day in the calendar. Use the ✕ button to remove an appointment from the list.

Account

An account is required to use appointments, calendars, and import/export features. The calendar itself — including navigation and the date converter — is fully accessible without an account.

To create an account, click Log In in the navigation bar and then Sign up here. Registration is currently available during the trial period.

Data policy: Calendarium Solaris stores only your username and password (hashed). Your calendar data stays on your own device. We do not track usage or share any data with third parties.