# Proofs

As soon as a timestamp is tamper-proof, meaning that it is embedded at least in one blockchain and has received enough confirmations from the network, you can download a corresponding proof.

You have the opportunity to request different proofs from our API, depending on the use-case.

Raw Proof

The raw proof is a XML file that contains the Merkle Tree, which is necessary for the calculation of the root hash.


You also have to possibility to download a PDF certificate from our API. The first page contains the timestamp information, which is followed by the raw proof. The last page contains the description about the manual verification. This certificate can be printed or handed out to your customers to proof that, i. e., a NDA was signed.


Keep in mind: You can only proof the existence of your data with a proof. Therefore, we recommend to store the proof next to your original un-touched data.

# Download a proof

Once your hash have reached status = 3, you can request a certificate that provides all timestamp information that is necessary to reproduce the timestamp without OriginStamp.

# Request

POST /v3/timestamp/proof/url (opens new window)

curl -X POST "http://api.originstamp.com/v3/timestamp/proof/url"\
     -H "Authorization: YOUR_API_KEY"\
     -H "Content-Type: application/json"\
     -d 'YOUR_PAYLOAD'

# Payload

  "currency": 0,
  "hash_string": "2c5d36be542f8f0e7345d77753a5d7ea61a443ba6a9a86bb060332ad56dba38e",
  "proof_type": 0

# currency

  • 0: Bitcoin
  • 1: Ethereum

# hash_string

The hash you want to obtain a proof for.

# proof_type

Specifies the proof type that should be returned. Possible value(s):

  • 0: Merkle Tree (XML file)
  • 1: Certificate (PDF)

# Response

Returns a JSON object that contains the URL to your requested proof. For the proof of a timestamp that is anchored in the Bitcoin blockchain it could look something like this:

    "error_code": 0,
    "error_message": null,
    "data": {
        "download_url": "https://api.originstamp.com/v3/timestamp/proof/download?token=<token>&name=proof.Bitcoin.2c5d36be542f8f0e7345d77753a5d7ea61a443ba6a9a86bb060332ad56dba38e.xml",
        "file_name": "proof.Bitcoin.2c5d36be542f8f0e7345d77753a5d7ea61a443ba6a9a86bb060332ad56dba38e.xml",
        "file_size_bytes": 0

# Download Request

This snippet shows how the proof file can be downloaded. Please note that the download link is only valid for 5 minutes.

     -H "Accept: application/octet-stream"