About Us

FAQ
For a document to be certified, ZenStamp creates a digital fingerprint (a SHA256 hash) and permanently save it as part of a transaction record on the Bitcoin blcokchain. The timestamp of the Bitcoin transaction becomes a timestamp for the document, which can prove the existence of the document at the transaction time.
No. The digital fingerprint for your document will be created in your web browser. We will only have access to the digital fingerprint. Your document itself will never be sent to our server. Therefore, your privacy is protected.
You should include the author information (such as the author's name, date of birth, ID number etc.) in your document. If the document to be certified is a text document, you can add this information in its contents. If it's other types of document such as photo, video, software etc., you can create a separate file containing the author information and then zip the two (or more) files together and submit the zip file to ZenStamp to get certified.
Once the digital fingerprint (SHA256 hash) of your document has been added to the Bitcoin blockchain, then your document has been certified. Using the Bitcoin transaction ID provided by us to you, you can use any Bitcoin blockchain explorer websites or software to verify that the digital fingerprint is showing in the "OP_RETUREN" or "RETURN" part of the Bitcoin transation (usually under the "Output Scripts" section). The "Received Time" of the Bitcoin transaction is the timestamp of your document.
First of all, you should save your original document and don't change its contents (A tiny change of its contents will change its digital fingerprint). Also, you should save the Bitcoin transaction ID (txid) for the transation that have its digital fingerprint info.
When you need to prove your authorship of the certified document, all you need to do is to provide an evidence showing the original document(s) (which include your authorship information) already existed at the time when the digital fingerprint was certified by ZenStamp. To do so, you can provide the origial document(s) and use a software to create a SHA256 hash from the docuement (or the zipped file). Then you need to provide the Bitcoin transaction ID (txid) provided by ZenStamp and look up that transaction using any Bitcoin blockchain explorer websites or software. Once you can show that your document's digital fingerprint is showing under the "OP_RETURN" field of the transaction record, you can prove that your document already existed at the time indicated by the Bitcoin transation's timestamp.
Yes. Your certification/timestamping information will be permanently recorded in the Bitcoin blockchain. Even if ZenStamp no longer exists, the information is still there and as long as you keep the corresponding transaction ID, you can use many websites/software to show the record. Actually, once your document has been certified, you won't need ZenStamp at all.