How it works

Not you, necessarily. You already know what you predicted. This is for everyone who wasn't there when you called it.

No. You can seal a prediction without signing in.

What you get instead of an account is a reveal link. That link is your only way back. Keep it where you can find it when the time comes. Your bragging rights depend on it.

If you want a prediction list across devices or set a display name for your predictions, sign in with Google. Google gives us your name and email address. Nothing more.

Go to the Seal page. No account required.

Write your prediction. A hunch, a conviction, whatever comes.

Choose a reveal date, or keep it manual.

Then seal it. ClldiT timestamps it, hashes it, and locks it away until reveal. Even you must wait.

Open the reveal link. If you chose a reveal date, the prediction opens once that moment arrives. If you chose manual reveal, use the button when you are ready.

Once revealed, the receipt shows what was written, when it was sealed, and the hash that lets others verify the whole affair.

Reveal the prediction and share the receipt. It shows what you wrote, when it was sealed, when it was opened, and the hash proving nothing shifted in between. Verification runs in your browser. Others need not take your word for it, which is rather the point.

Tap Share this receipt → for a link anyone can open, no account needed. For Instagram, tap Share image (Instagram) instead. Mobile shares it directly. Desktop downloads the image.

Use whichever you prefer. Either way, your "Called it!" has a receipt.

When you seal a prediction, ClldiT creates a SHA-256 hash from three things taken together: the prediction text, its unique ID, and the exact time it was sealed, down to the millisecond.

That hash is a digital fingerprint tied to all three. Change the text, the ID, or the timestamp, and the fingerprint changes with it.

The full 64-character hash appears on every revealed receipt. Tap Verify → to check it yourself. The calculation runs in your browser using the Web Crypto API, not on our server. One need not take our word for any of it.

This only applies if you chose manual reveal. If you chose a date, your prediction unlocks automatically on that date. No action needed.

For manual predictions: your prediction has an expiry date, 90 days by default (you can change this when sealing). If you have not revealed it by then, it expires and can no longer be revealed.

The expiry date is shown on the sealed prediction page.

Cryptography explanations are perhaps best left to people who haven't, on at least one occasion, forgotten how locks work. Nevertheless.

The hash, the prediction ID, and the timestamp are all publicly visible on a sealed prediction. Anyone motivated enough can test guesses against the hash. The content is hidden in the interface. It is not hidden from a determined guesser with a fast computer.

A secret random value in the hash, a "salt," would prevent this. The reason there isn't one: whoever holds the salt has to be trusted. The current design requires trusting nobody. Anyone can verify the hash themselves, with their own computer, right now. An imperfect choice, made with open eyes.

For state secrets, classified materials, or anything you'd be upset to see on the internet one day: we are not the right tool. We are, with respect, barely the right tool for anything. But for "Called it!", we are precisely the right tool!