All your calendars, in one place. With nobody in between.

WeekEventInvitationsRepeatsConnectMonth

Every account in one week

Each account has its own ink, shown on the edge of its events, so you can tell work from home at a glance. The red line is now. Drag on the grid to create an event, drag an event to move it, pull its edge to make it longer.

Everything about an event, one click away

Click an event to see when it is, which calendar it's in, who's invited and how many accepted. Join the call in 1B Talk, Teams, Meet or Zoom, edit it, or — if you have them — take notes in 1B Note and write to the guests with 1B Mail.

What needs an answer, first

Invitations from every account wait in one tray, with the number on the title bar. Each one shows where it came from and whether it overlaps with something you already have, on a small timeline. Accept, Maybe or Decline, with an optional note for the organiser.

Repeat it however you need

Every day, every weekday, weekly on several days, monthly on day 15 or on the first Monday, yearly — ending never, on a date or after a number of times. When you change one event of a series, choose This event, This and following events, or All events.

Your calendars, where they already are

Sign in to Google or Microsoft on their own page in your browser, connect iCloud with an app-specific password, add any CalDAV server with its address, or subscribe to an .ics link. Or keep a calendar only on this computer.

The month, the agenda and the day

Six weeks at a glance, with all-day events as bars and timed ones as dots; the next 30 days as a printed-style agenda; or a single day hour by hour. Search everything with Ctrl K.

• 01Byte servers between you and your calendars
• 30 daysin the trash for anything deleted or overwritten
• 5ways to connect: Google, Microsoft, iCloud, CalDAV and .ics
• 21languages, settings included

Counted in the code of 1B Calendar 0.1: the accounts, the trash (30 days) and the five kinds of connection. The app syncs every 5 minutes and right after every change you make. The Linux packages were installed and opened on Ubuntu 22.04 and 24.04, Debian 12 and 13, Linux Mint 22, Fedora 43 and 44, openSUSE Tumbleweed and Arch.

1. Straight to each provider

   Google, Microsoft, Apple and your CalDAV server are reached directly from your computer, over HTTPS. There's no 1Byte server in the middle and no 1Byte account to create.

2. Your change first, then the sync

   What you do is saved on your computer at once and sent to the service right after, before anything is downloaded. If the same event changed elsewhere at the same time, the service's version wins and yours is kept in the trash.

3. Nothing disappears for good

   Anything you delete, or that's overwritten by a conflict, stays in the trash for 30 days. Right after creating, moving, changing or deleting, Undo puts it back.

• Undo

  Created, moved, changed or deleted something by mistake? Press Undo in the notice that appears.

• Trash for 30 days

  Deleted events, and your version when there's a conflict, wait in Settings › Trash with a Restore button.

• Search with Ctrl K

  Find any event by its title, place or notes, across every account.

• Reminders

  System notifications for your reminders while 1B Calendar is open, with a default reminder for new events.

• Time zones

  Each event keeps its own time zone, and repeats stay right when the clocks change.

• Inks and themes

  Pick an ink for each calendar, hide the ones you don't need and choose light, dark or the system's theme.

• Keyboard shortcuts

  N new event, T today, D, W, M and A for the views, I for invitations, the arrows to move.

• .ics files

  Open an .ics file with 1B Calendar to add its events or answer the invitation inside; export any event as .ics.

• Works with 1B apps

  Shares your agenda with 1B Dock and 1B Mail on this computer, sends invitation replies through 1B Mail and takes meeting notes in 1B Note.

• Signed updates

  Every new version is signed by 1Byte Systems and checked before it installs, when you say so.

• Your week, your way

  Work week or full week, the day your week starts, 12- or 24-hour time, the view it opens in and week numbers.

• Windows and Linux

  The same app for Windows 10 and 11 and for Linux, in 21 languages.