Turn a Google Sheet into calendar events

There's no button that takes a Google Sheet into Google Calendar, and the add-ons that bridge the gap generally ask for access to your Drive and calendar. Koyomi's route needs none of that: File → Download in Sheets, convert here, import the .ics.

A student with a semester's syllabus in a Sheet — assignment, course, due date, maybe a time — downloads it as CSV (current sheet) or as .xlsx, drops it here, and gets one event per deadline. Dates typed however the professor wrote them ("Sep 14", 14/09/2026, 2026-09-14) are recognized, and day-first or month-first is inferred, with an override if the guess is wrong.

Because the .ics carries stable event IDs, updating the Sheet and repeating the download-convert-import loop updates the existing events in Google Calendar instead of duplicating them — useful when due dates move. Import steps for Google Calendar are below.

After you download the .ics

Google Calendar

  1. Open calendar.google.com on a computer (the mobile apps can't import files).
  2. Click the gear → Settings → Import & export.
  3. Select the .ics file, choose which calendar to add the events to, and click Import.

Frequently asked questions

Should I download the Sheet as CSV or Excel?
Either works. CSV is fine for a single sheet. Choose Excel (.xlsx) if you want to keep several tabs in one file and pick the tab here, or if your dates are real date cells you'd rather not have reformatted.
Does this stay in sync with the Sheet afterwards?
No. It's a one-way conversion: the .ics reflects the Sheet at the moment you downloaded it. To push changes, download and convert again; re-importing updates the existing events rather than duplicating them in most calendar apps.
Can I import the .ics into Google Calendar from my phone?
Not through the app; Google Calendar only imports files on the website. Do it once from a computer, and the events appear on your phone through normal sync.
Is there a Google Sheets add-on?
No, deliberately. Koyomi never asks for access to your Google account. Download the sheet, convert it in your browser, import the file. Nothing leaves your machine.
Is my spreadsheet uploaded anywhere?
No. Parsing and the .ics file are produced entirely in your browser — the file never leaves your device. That's also why there is no size limit, no queue and no account.
Is this really free?
Yes. Every input format, every option, no sign-up, and nothing added to the calendar file.
Does it support recurring events?
Not yet. Each row becomes one single event. For a weekly class or shift, put one row per occurrence — filling a date column down in a spreadsheet takes seconds.