Privacy Policy

Last updated 21 August 2026

CalendarHippo turns school emails, flyers, photos and voice notes into calendar events, over WhatsApp. To do that it has to handle messages about your children. This page says exactly what it holds, who else sees it, and how long it is kept. It describes what the software actually does, not what we reserve the right to do.

CalendarHippo cannot read your existing calendars. It asks Google for one narrow permission, calendar.app.created, which allows it to create new calendars and manage events only on the calendars it created itself. Your work diary, your personal calendar, and anything you had before are invisible to it. This is enforced by Google, not by our restraint.

What we collect

Your WhatsApp phone number, so we know which family a message belongs to.
The messages you send us, and the replies we send you.
Things you forward or attach — emails, photographs of flyers, PDFs, voice notes.
Your children's first names or initials, as you give them to us, to label their calendars.
Details of the events you approve — title, date, place, and what to bring.
Your home address, but only if you ask for drive times, and only after we ask you for it.
Your settings — timezone, quiet hours, what time the evening rundown arrives.

We do not ask for, and have no use for, dates of birth, school records, medical information, or payment details.

What we do with it

We use it to do the thing you asked for: read what you sent, work out the dates, propose events, and write the ones you approve to your calendar. We do not sell it, we do not advertise against it, and we do not use your family's messages to train AI models.

Who else sees it

Some processing needs specialist services. Each receives only what that task requires.

Service	What it receives	Why
Anthropic (Claude)	Message text, and images of flyers	To understand what you wrote and read what a flyer says
Groq (Whisper)	Voice notes	To turn speech into text
Google Calendar	Events you have approved	To write them to your calendar
Google Maps Platform	Event addresses, and your home address	Drive times, and the weather for an event's day
Meta (WhatsApp)	The messages themselves	WhatsApp is how you talk to us
Cloudflare	Emails you forward	To receive them and pass them on
Fly.io	Hosting for the service and its database	Where CalendarHippo runs

Anthropic and Groq are used to process your content in the moment, not to train their models on it.

How long we keep it

Conversations: 30 days. Older messages are condensed into a short summary rather than kept in full, so the assistant remembers the gist without holding the words.
Flyers, photos and voice notes: 30 days, then deleted automatically.
Your settings, children and calendar links: for as long as you use CalendarHippo.
Calendar events: these live in your Google account and are yours. Removing CalendarHippo does not delete them.

How it is protected

The key that lets us reach your Google Calendar is encrypted before it is stored, with AES-256-GCM.
Each family's data is separated inside the database itself, so one family's records cannot be returned by a query about another. This is enforced by the database, not only by our code.
Messages arriving from WhatsApp are cryptographically checked to confirm they genuinely came from WhatsApp.
Text written by other people — a forwarded newsletter, a flyer — is marked as untrusted before the AI reads it, so a message cannot instruct the assistant to act against you.

What you can ask for

Message the assistant, or email hello@calendarhippo.com, and we will:

tell you what we hold about your family;
correct anything that is wrong;
delete your family's data entirely;
disconnect Google, which stops all calendar access immediately.

You can also revoke our access yourself at any time, without asking us, at myaccount.google.com/permissions. Deleting your data does not remove events already written to your own calendar — those are yours to keep or delete.

Children

CalendarHippo is for parents. Children do not have accounts and do not message the assistant. We hold a child's name or initials and their activities only because a parent chose to tell us, so their schedule can be organised.

Google user data

CalendarHippo's use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements. Specifically: Google Calendar data is used only to provide the features described on this site, is never sold, is never used for advertising, and is never used to train generalised AI models.

Changes

If this policy changes in a way that affects what we do with your data, we will tell you in the chat before it takes effect.

Who we are

CalendarHippo is currently in private testing with a small number of families and is operated from Hawaii, United States. Contact: hello@calendarhippo.com.