Prior Art: Signed Hash Database

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Anyone is free to post a hash, along with a signature. Use of this site is at your own risk, and I provide no guarantees as to its stability or fitness for purpose. To use this site, create a document containing your idea, and append at least 74 random characters. Create a hash using SHA-2. Sign using GPG. Then upload both the hash and the signature. If at some later point you need to prove when you wrote the intial file, you can use the signed hash here, together with the upload time stamp, to prove a bound on when you wrote it. Simples! Why 74 random bits? Well, just for your own piece of mind. 74 ASCII characters take more than 512 bits to represent (518 to be exact). If they are chosen uniformly at random there is no way to compress that part of the document below 518 bits, which is longer than a SHA-2 hash. Thus there is no way you could have been tricked into uploading a compressed version of your document.

Current Entries

Viewing entries 11 through 20 (Total entries: 1695)

Hash:
Waylon
Signature:
Отличное kazino olimp, качественный контент.
Большое спасибо!
kazino olimp
Monday, February 23 2026 - 06:39 PM
Hash:
Millie
Signature:
Sayt çox funksionaldır.

1win
Monday, February 23 2026 - 01:33 PM
Hash:
Maddison
Signature:
소개할게요클럽정보 구해요그치만 예약 정보주세요고마워요
룸술집
추천주점
Saturday, February 21 2026 - 12:34 AM
Hash:
Shonda
Signature:
Party Snapps Photo Booth OⲤ| Pһoto Booth Rentaⅼ Orange County
12911 Dungan ᒪn, Garden Grove, CA 92840
дедицира
Thursday, February 19 2026 - 05:49 AM
Hash:
Tegan
Signature:
ΕΠΙΠΛΑ ΓΕΩΡΓΑΝΤΑΣ
ΠΑΝ. ΓΡΗΓΟΡΙΑΔΗ 3
ΩΡΑΙΟΚΑΣΤΡΟ, ΘΕΣΣΑΛΟΝΙΚΗ
Τ.Κ. 57013
Τηλέφωνο
23120 08844, 6976590826
έπιπλα θεσσαλονίκη
Wednesday, February 18 2026 - 02:21 PM
Hash:
Maximo
Signature:
스크랩했어요가라오케정보 알려주세요뿐만아니라 행사 설명해주세요감사해요
동성로노래방
대구 주점
Tuesday, February 17 2026 - 07:00 AM
Hash:
Francesca
Signature:
Для тех, кто ищет уникальные товары, платформа (/|\✭/|\) KRAKEN актуальные
зеркала 2026 ➾ рабочие ссылки для доступа к площадке предлагает
отличные условия. Здесь доступны коллекционные вещи, техника и
стильная одежда. Удобный интерфейс и простота
использования платформы делают покупки лёгкими.

Кракен обеспечивает безопасность сделок, что даёт
уверенность новым покупателям.
Именно (/|\☆/|\) Зеркала KRAKEN 2026 - надежный вход
() удерживает позиции лидера в
онлайн-шопинге.
Saturday, February 14 2026 - 02:25 PM
Hash:
Maynard
Signature:
파악했어요 실시간중계 사이트 다만 캡처해도 되나요 굿굿
KBO무료중계
밤경기중계
Thursday, February 12 2026 - 07:37 PM
Hash:
Freddie
Signature:
Актуальный топ лучших онлайн казино: куда играть в этом сезоне драгон мани официальный сайт
Monday, January 26 2026 - 07:25 AM
Hash:
Vernell
Signature:
Super platformadır! Uğurlar!

Mostbet mərclər [home]
Sunday, January 25 2026 - 09:38 PM
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