Messages that arrive exactly when they should

Some words are written years before they're meant to be read: a letter for your daughter's eighteenth birthday, advice for a future co-founder, the story you want told in your own voice. A digital time capsule holds them sealed — encrypted, private, unread — until the moment you chose.

Two kinds of "later"

A date you set. Pick a specific day — a birthday, an anniversary, a decade from now — and the capsule releases then. Until that day the recipient doesn't even know it exists.

Only if you're gone. Some messages should arrive only if you can't deliver them yourself. Put the capsule on a dead-man trigger instead: as long as you answer a periodic check-in, it stays sealed forever; if you permanently stop, it releases to the person you named.

What people seal

Sealed means sealed

A letter this personal shouldn't sit readable on someone's server for a decade. Capsulene encrypts capsule contents in your browser before upload (AES-256-GCM) — nobody, including us, can read a sealed capsule. You can edit, pause, or delete it at any time before release.

Write it now. Decide when it arrives. Free to start.

Seal a time capsule

Frequently asked questions

What's the difference between a time capsule and a dead man's switch?

A time capsule opens at a date you set, no matter what. A dead man's switch opens only if you stop confirming you're okay. Capsulene supports both: pick a specific date, or a recurring check-in rhythm.

Can the recipient see the message before it opens?

No. The recipient isn't notified until the capsule releases, and contents are encrypted in your browser before upload — there is nothing readable to find in the meantime.

Can I edit or cancel a scheduled message?

Yes, at any point before release: edit the contents, change the date or recipient, pause it, or delete it entirely.

Related: family emergency access · how the dead-man trigger works