A calendar for Windows with no account, no sync and nothing phoning home. Your appointments live in a single file on your own machine, and you can put a password on it. Once it is locked, that file is encrypted at rest with SQLCipher using AES-256.
Unlocked it is an ordinary SQLite database, so you can read it, back it up, or carry it to another machine with a copy and paste. No service to sign up for, no telemetry, no ads.
killendar.net | part of Killer Tools
- Four views - month, week, day and agenda, with one shared previous / next / today control.
- Appointments in the sidebar, not a dialog box. Title, start and end, all-day, location, description and attendees, with the panel sliding out from the icon rail.
- Overlapping appointments sit side by side in the week and day views, so a double-booked hour shows both rather than hiding one behind the other.
- Repeating appointments - daily, weekly on the days you tick, monthly or yearly, every N of those, ending never, after a set number, or on a date. A series is one stored appointment whose dates are worked out as the calendar draws them, so editing a weekly standup is one edit and a series with no end date costs nothing. Editing or deleting one date asks whether you mean just that date or the whole series.
- Drag to move - drag an appointment to another time or day in the week and day grids, or to another date in month view. One date of a series moves on its own, as an exception; right-click any of its dates for "Edit the series" when you mean the whole thing.
- A 5-day work week toggle in the week header drops Saturday and Sunday, and the grid density control steps the hour grid from hour lines down to quarter hours.
- Import and export in the formats people actually hand you - iCalendar (.ics, RFC 5545, written from scratch with no external dependencies) both ways; CSV both ways in Outlook's column format, one row per date; a saved email invite (.eml) in; and a month-by-month web page out, carrying all six themes and a print stylesheet so print-to-PDF covers printing. Export asks whether you mean the whole calendar or a date range. Repeats survive the .ics round trip, including dates you deleted from a series or edited on their own. Import skips anything already in your calendar, and says what it could not keep rather than swallowing it: repeat rules too exotic to draw, entries with no readable date, and tasks or journal entries Killendar has nowhere to put are all counted and reported.
- Optional encryption - the lock button in the title bar puts a password on your Killendar and it is encrypted at rest with SQLCipher (AES-256). Opt-in: no password means a plain SQLite file.
- As many Killendars as you like - work, on-call, family. Create, rename, delete, load and switch from the Killendars button in the title bar. Each file has its own password, or none.
- Double-click a
.kcaland Killendar opens it. Registered for your user only, no elevation, removed on uninstall. Only one instance runs, so two copies never write to the same calendar. - Six themes - Dark, Light, Black, Blood, Greed and Cyanotic - with six accent hues on the first three, switchable at runtime. Ships on dark with the red accent, the same red as the wordmark.
- Ten languages, switchable from the rail without a restart.
- Keyboard driven - single keys for everything, no modifier gymnastics.
- Verified code signing shown in the About card, checked with WinVerifyTrust rather than just read off the file, so a tampered build cannot display a signer it does not own.
Portable - download Killendar.exe and run it. It is a single self-contained file; nothing is
written outside your profile until you ask for it.
Installed - run the exe and use the install prompt. Per-user goes to
%LOCALAPPDATA%\Programs\Killendar; the all-users option installs to Program Files and prompts for
elevation once.
Silent / deployment - Killendar.exe /silent installs machine-wide with no UI, for winget,
Chocolatey and RMM tools. Uninstall from Add/Remove Programs, or Killendar.exe /uninstall.
Uninstalling never deletes your appointments.
| Key | Action |
|---|---|
N |
New appointment |
T |
Jump to today |
Left / Right, or , / . |
Previous / next period |
M W D A, or 1 2 3 4 |
Month / week / day / agenda |
B |
Show or hide the appointment panel |
F1 |
Keyboard shortcuts overlay |
F12 |
About |
Esc |
Close the panel or overlay |
Ctrl+I / Ctrl+E |
Import / export |
Single keys only fire when you are not typing in a field. Esc always works.
| What | Where |
|---|---|
| Appointments | %APPDATA%\Killendar\*.kcal (starts as Default.kcal) |
| Theme, accent, language, date format, window position | %LOCALAPPDATA%\Killendar\settings.json |
A .kcal file is a Killendar. It is an ordinary SQLite database, so any SQLite tool will open it -
nothing here is a private format you cannot get your data out of. Times are stored in UTC, so a
calendar carried to another timezone still says the right thing, while all-day entries stay on the
date you put them on.
Killendars are per-user. Installing for all machines still gives every user who signs in their own fresh Killendar.
If you used a build from before the database (appointments in events.json), the first launch moves
them into Default.kcal for you and keeps the old file as events.json.migrated rather than
deleting it.
The lock button in the title bar sets a password. The Killendar is then encrypted at rest with SQLCipher: AES-256 with per-page HMAC-SHA512, and SQLCipher's own PBKDF2 key derivation. The same button changes the password, or removes it and rewrites the file as plain SQLite. Encryption is opt-in; a Killendar with no password is an ordinary readable database.
An encrypted Killendar asks for its password when the app starts. There is no recovery. If the password is lost the appointments are lost - that is what the encryption is for. The locked file is renamed aside and kept on disk rather than deleted, and a new empty Killendar opens in its place.
What this does not protect:
- Nothing is protected while Killendar is open and unlocked.
- Not against a keylogger, a memory dump, or anyone who has your password.
settings.jsonstays plaintext. It holds theme, accent, locale, date format, window position and which prompts you have dismissed - nothing about your appointments.- iCalendar export is plaintext by definition. Exporting an encrypted Killendar to
.icswrites an unencrypted copy of it. Killendar warns you the first time you do this and lets you turn the warning off; it never blocks the export, because handing a colleague an.icsis the whole point of having one.
Requires the .NET Framework 4.8 developer pack and Visual Studio 2022 (or the Build Tools).
dotnet build Killendar.csproj -c Release
brand/ holds the working artwork and is not tracked. Everything the app consumes is generated out
of it into Resources/, which is tracked, so a fresh clone builds without it.
GPLv3. See LICENSE.