WattShed Attest
Fix the facts of a completed case, and prove they never moved.
Enter the facts of one completed case: a project ID, the program it ran under, the verified annual kWh it saved, when it finished, and anything else worth attaching. Stamp them, and this tool hands back a serial and a digest computed from exactly those fields at exactly that moment. Re-enter the same fields and the same stamped time later, and the same serial comes back only if nothing changed.
Everything computes in this browser. Nothing you type is sent anywhere, and WattShed keeps no copy of a stamped record once you leave this page. Download the record as JSON or print it before you go; that copy, kept by you, is what a later check runs against.
This produces an audit record of the fields you entered, not a determination that those facts are real. It proves a set of fields has not moved since it was stamped. It does not prove a project happened, that a savings figure is accurate, or that a program paid out.
WattShed Attest
Stamp a new record, or check one you already have
Stamp mode
Enter the facts of a completed case
Every field below becomes part of what gets hashed. Change anything after stamping and the record shown stops matching what's in the form; stamp again once the fields are final.
Nothing you type here is sent anywhere. It's computed in this browser, and WattShed keeps no copy of it once you leave this page.
Enter a case's facts and stamp them to see the record here.
Nothing is stamped until you press the button below. Nothing is sent anywhere either way.
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What a stamp proves
Three things worth knowing before you rely on a serial.
What it proves
That the project ID, program, verified annual kWh saved, completion date, and any notes you entered existed together at the stamped time, and have not changed since. Re-enter them later and the same serial comes back only if nothing here moved.
What it does not prove
That any of it is true. A stamp cannot confirm a project actually happened, that the savings figure is accurate, or that the named program paid out. It proves the record was not altered after it was stamped, nothing about the case it describes.
Why keeping the record matters
WattShed keeps nothing: no copy of a stamped record exists here once the tab closes. The downloaded JSON, or a printed page, is the only copy that will ever exist. Lose it and there is nothing left to check a later claim against.
A matching serial confirms the record you're holding is exactly the one that was stamped. It confirms nothing about whether the case it describes is real.