Proof of existence

Timestamp any file with @beat — free and public. Your file never leaves your device; only its SHA-256 is recorded. Later, prove the document existed at that moment.

Drop a file here, or click to choose — hashed locally (SHA-256).

Your timestamp is recorded instantly — the extra seals are added later

Right away, when you stamp: your hash, its @beat and UTC time, and its position in the append-only hash-chain. That alone already proves the document existed at that moment.

After the week ends — once the current week closes (the following Monday, 00:00 UTC) its weekly Merkle root is frozen, and three independent layers are added on top:

So a fresh certificate that shows “pending — week still open” is completely normal. Come back after your week has ended and been sealed, then verify again or download the certificate once more (or scan its QR code) — the signature, Bitcoin attestation and bank anchor will then appear. The timestamp itself never changes.

Weekly Hash Anchoring

Each week's Merkle root is anchored against an independent bank reference — a separate, timestamped record that the week's log existed by that date.

2026-09-15 · week 2026-W37
6e6195e7b3fc68759313b51ad9cdc9561aa0f2ea7ac3543ac7fc2335b6b069de
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1174262612
2026-09-10 · week 2026-W36
9f4047d4e380e4aafe5c74e5c79adaea91e4e17d06451d6b287942206402cb9b
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1169672496
2026-09-01 · week 2026-W35
5e063fd45948dff2c7c514386acc1d876132566eca203f5f4bcf7e9c8c85067d
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1165796278
2026-08-25 · week 2026-W34
ff3a763358a943dc75e4b0a485f135047ecb637ab47ae6eab1d8ced1888c8e17
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1161577508
2026-08-18 · week 2026-W33
7a1465c1c122c9f788f6e10d563f440b3784b111dfbddcef3ac020278d07ce96
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1156833423
2026-08-10 · week 2026-W32
d9c958ab2f36d533bd7a054f89348324a973cd7a3fa0141a80503b604c41d02f
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1152611848
2026-08-04 · week 2026-W31
ec00a1a0bc015e4b13feda72fe0dd859507d48f859da81498c2a1eceab970253
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1148932604
2026-07-28 · week 2026-W30
gfKbhyyKvpQMYvOe9zWGRoyMHno0VFWAznoVD7GAHuYrXb2g1bIlwhr+z6ard6w+
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1144955485
2026-07-23 · week 2026-W29
72c71c70291a6d3cebf5e84ebe0a01163187a56ccd469785beb06b79346f292a
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1141610457
2026-07-06 · week 2026-W27
a66f790ca3fdd097dadf24226139aa148ae9b84e29e8aec53accf5e22b594fbf
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1132054035
2026-06-30 · week 2026-W26
b460cb716fbf3481480b428f97d7ec115d8816f0fcb3669a85e03774065256b8
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1127113185
2026-06-23 · week 2026-W25
1b33c081be206b028d508be5046a3da6a195448fbded7d54a6f2e02d13a5749d
Anchored by: Swissquote Bank SA (Swiss bank · Status: ✓ confirmed · Bank ref: 1122189662

How it works

1. Your browser computes the file's SHA-256 — the file stays on your device.

2. The hash is recorded in an append-only, hash-chained log with its @beat and UTC time.

3. Each week all hashes are combined into a Merkle root, signed with our Ed25519 key and anchored externally — against an independent bank reference and in Bitcoin via OpenTimestamps.

4. Anyone can later verify a file's hash, its timestamp, its inclusion proof up to the anchored root, the signature, and the Bitcoin attestation (downloadable .ots).

This attests existence at a point in time and integrity — not authorship or authenticity of the content.

Sharing a stamped photo through a messenger? Send it as a document/file — apps that recompress images change the bytes, and the hash of what arrives no longer matches the stamped original.

Want the exact algorithm — leaf and node hashing, the signed message, how to recompute an inclusion proof? Read the full proof specification.

Proof answers “this existed before then”. Its mirror image answers “this cannot be read until then”: a time-sealed envelope that opens only after a chosen @beat, and only when independent key holders come together — so nobody can open it early, ourselves included. Live and public today for developers; the one-click flow lands here next.

Weekly Merkle roots are signed with our Ed25519 key. Public key: YNVYXDyg3hQGM3F+/ec+ZNmeN1JI/hZX+CxLqyJdyN0=