Time Capsule
Encrypt messages and files. Lock them until the future.
Click to upload files (max 10MB per file)
Your time capsule will be encrypted with AES-256-GCM and downloaded as a .xtc file. Keep this file and password safe. No data is sent to any server.
What is the Time Capsule?
The Time Capsule is a digital time capsule tool with encryption. Write a message to your future self, optionally add files, set an unlock date and password. The tool creates an encrypted file that can only be opened after the chosen date with the correct password. Perfect for personal reflections, goal tracking, or emotional time travel.
Practical Use Cases
New Year's Resolutions with Accountability
On January 1st: Write your goals for the year ("Lose 10 kg", "Find new job"). Unlock date: December 31st. Throughout the year, you forget the capsule. On Dec 31st: open, read, compare with reality. This confrontation is more honest than mental retrospection – you can't sugarcoat what you originally wrote.
Therapeutic Self-Reflection
During difficult life phases (depression, grief, illness): write how you feel NOW. Unlock: 6 months later. In 6 months, you open the capsule and see: "I made it through, I've grown." The tool documents emotional journeys objectively – no nostalgia filters, only raw truth.
Family Time Capsules for Children
Parents create a capsule for their 5-year-old child, unlock: when the child turns 18. Content: letters from parents, children's drawings, first words, videos. 13 years later: the child opens the capsule and sees how parents thought about them when they were small. Emotional, unchangeable, authentic.
Startup Founder Documentation
Day 1 of the startup: founders write their vision, fears, hopes. Unlock: 5 years later or exit. If the startup succeeds: the capsule shows how naive/optimistic you were. If it fails: you see where the warning signs were. Whatever the outcome – the capsule is an honest mirror of founding reality.
Relationship Milestones
Newly in love couples write a capsule together: "Why we love each other, our dreams together". Unlock: 10-year anniversary. 10 years later they open the capsule: some dreams came true, some didn't, but the raw emotion from the beginning is preserved. It's an anchor to what originally united them.
Frequently Asked Questions (FAQ)
How secure is the encryption?
The Time Capsule uses browser-native WebCrypto API with AES-GCM encryption. This is bank-grade encryption, the same technology as HTTPS. Without the password, the capsule is practically uncrackable (would take centuries with current hardware). BUT: security depends on your password. Strong passwords = strong security.
What happens if I forget the password?
The capsule is lost forever. There's no "password reset" mechanism – that would require backdoors, compromising security. Therefore: choose a password you can remember (but still strong enough). Write it on paper and store it securely if needed. No cloud storage of passwords!
Can I open the capsule before the unlock date?
No, the tool prevents unlock before the chosen date. That's the whole point: forced patience. If you could open the capsule immediately, it would just be an encrypted document, not a time capsule. The unlock date enforcement gives the capsule its emotional value – you must wait to see what your past self wrote.
Is my capsule data uploaded anywhere?
Never. Encryption happens entirely in your browser. The encrypted file is saved as a download – on your hard drive, not in the cloud. There's no server communication. You're responsible for storing the file (local backup recommended). 100% offline, 100% private, 100% GDPR/DSGVO compliant.
Can I add photos and videos to the capsule?
Yes, the tool supports file uploads. You can upload images, videos, PDFs, etc. Note: large files (videos over 100MB) can encrypt slowly and the resulting capsule file is very large. For massive video archives, use external storage (USB stick in safe) and write in the capsule only "Video is on USB in safe".
What if the website doesn't exist in 10 years?
The encrypted file remains valid, but you'd need the tool to decrypt it. Therefore: optionally save the entire tool website locally (browser: "Save page as"). The capsule file is standards-compliant and could theoretically be opened with any tool supporting the same encryption standard – but practically, local tool backup is the safest option.
Can I share the capsule with other people?
Yes, send them the encrypted file + the password (separately, not in the same email!). Both must wait until the unlock date. This is perfect for couple capsules or family capsules. Important: share password and file via different channels (e.g., file via email, password via Signal or in person).
What should I write in a Time Capsule?
The beautiful thing about Time Capsules: there are no rules. Write about your current feelings, fears, hopes. Write mundane details ("I'm listening to song X on repeat right now") that become nostalgic later. Ask your future self questions ("Did you make it?"). Be honest – you're only reading it yourself. The best Time Capsules are raw, unpolished, and authentic.
Privacy Guarantee
- ✓ All data stays local in your browser during creation
- ✓ Encryption happens client-side with WebCrypto API
- ✓ No transmission to servers or cloud services
- ✓ Encrypted capsules are saved as local downloads
- ✓ No tracking, no analytics, no cookies
- ✓ 100% GDPR/DSGVO compliant by design