What we keep, why, and for how long

Kept Letter exists to hold something private until the right day. This page says plainly what that involves.

What we collect

From the person who starts a capsule: their name, email address, the capsule's title and opening date, and their time zone (so it opens on the right morning).
For each recipient: the name and up to three email addresses the organizer enters.
From each writer: the name they sign with, their letter, and any photos, voice note or video they add.
Records of what happened to a capsule (created, sealed, paid, delivered, opened or declined), kept so we can show you its status and prove delivery.
We do not ask for accounts or passwords, and we do not use advertising or tracking cookies.

How we use it

Only to keep and deliver your capsule: to show it to the people who hold its links, to email the organizer their private link, and to email recipients on the opening day. We do not sell personal data, show ads, or use letters, photos or voice notes to train AI models.

Who can see a capsule

Access works through private links. Anyone who has a link can do what that link allows, so keep them to yourself.
Before the opening day, letters cannot be read through Kept Letter by anyone, including the organizer. Each writer can see and download their own letter.
On the opening day, each recipient decides whether to open the capsule. Letters are shown only after they accept.
A small number of people who run Kept Letter can access the database to keep the service working. We look at capsule contents only if the law requires it or to investigate abuse reported to us.

Where it is stored

Letters and records are stored with our database provider, Supabase, in Tokyo, Japan, encrypted at rest. Photos, voice notes and videos are kept in private storage and shown only through links that expire after an hour. Email is sent through Resend. Payments are handled by Stripe; we never see or store card numbers. The site is served by Vercel.

How long we keep it

Until the capsule is delivered and for as long as recipients may want to come back to it. A writer can remove their own letter until the capsule is sealed. To have a capsule deleted after it is delivered, contact us from the organizer's email address.

Your rights

You can ask to see, correct or delete personal data about you. Organizers can download their capsule and change recipients' addresses from their private link at any time. If you are in the EU, UK or California, you have the rights given by the GDPR, UK GDPR or CCPA, and we will honour them.

Who we are

Kept Letter is run by DOPPO, a small company being set up in Tochigi, Japan. Write to us through our contact page.

Children

A capsule may be written for a child, but the person who starts it must be an adult. When a capsule is for a child, add a parent's email address as one of the recipient's addresses.