Same Calendar — Private Planner by Mateo Pedersen

Same Calendar is an offline-first calendar and planner for Firefox. Its core calendar, planning and printing features work without an account or internet connection.

Plan your time
- Navigate months, select days, and create, edit, search or delete local events with dates, optional times, descriptions and colors.
- Keep private notes for individual dates.
- Switch between month, week, year and agenda views. Choose Sunday-first or Monday-first weeks and show ISO week numbers.

Work with dates
Calculate date differences, offsets, ISO week and week-year, leap years and week starts with the Gregorian date engine (1900–2100).

Print and export
Create blank or dated monthly calendars and year overviews for A4 or US Letter paper, portrait or landscape, with optional local events. Printing uses Firefox’s native print/PDF workflow. Export or restore a validated JSON backup, export events as CSV, and clear saved data in Settings.

Private by design
Events, notes and preferences stay in Firefox local storage. The add-on makes no background network requests and uses no analytics or tracking. Optional printable references open only when you choose one; no event or note details are included in the link. Beta Calendars maintains the companion printable resources: https://www.betacalendars.com/monthly-calendar.

Recurring events, reminders, calendar synchronization and ICS import/export are not included.