# Creating a timestamp

# Calculate SHA-256

To create a timestamp, you must first calculate the SHA-256 hash of your record. There are standard libraries for all programming languages:


public String getSHA256(byte[] input) {
    MessageDigest digest = MessageDigest.getInstance("SHA-256");
    byte[] encodedhash = digest.digest(input);
    return bytesToHex(encodedhash);

private static String bytesToHex(byte[] hash) {
    StringBuffer hexString = new StringBuffer();
    for (int i = 0; i < hash.length; i++) {
    String hex = Integer.toHexString(0xff & hash[i]);
    if(hex.length() == 1) hexString.append('0');
    return hexString.toString();


static string ComputeSha256Hash(string rawData)  
    // Create a SHA256   
    using (SHA256 sha256Hash = SHA256.Create())  
        // ComputeHash - returns byte array  
        byte[] bytes = sha256Hash.ComputeHash(Encoding.UTF8.GetBytes(rawData));  

        // Convert byte array to a string   
        StringBuilder builder = new StringBuilder();  
        for (int i = 0; i < bytes.Length; i++)  
        return builder.ToString();  


import hashlib


# Submit your hash

# Request

POST /v4/timestamp/create

curl -X POST "http://api.originstamp.com/v4/timestamp/create"\
     -H "Authorization: YOUR_API_KEY"\
     -H "Content-Type: application/json"\
     -d 'YOUR_PAYLOAD'

# Payload

  "comment": "test",
  "hash": "2c5d36be542f8f0e7345d77753a5d7ea61a443ba6a9a86bb060332ad56dba38e",
  "notifications": [
      "currency": 0,
      "notification_type": 0,
      "target": "mail@notification.de"
      "currency": 0,
      "notification_type": 1,
      "target": "https://webhook-notification.url"
  "url": "string"

# comment (optional)

You can add a short comment (max. 256 characters) which can be used for indexing and searching (privacy-preserving).



# hash (required)

Hash in HEX representation. We suggest to use SHA-256. This hash will be aggregated and included into the blockchain.



# notifications (optional)

Add a list of notifications to your submission. Our system will notify each specified target with the corresponding timestamp information when the status is verified in a Blockchain.

Example for a mail notification on Bitcoin

  "currency": 0,
  "notification_type": 0,
  "target": "no-reply@originstamp.com"

Example for a URL webhook notification on Ethereum

  "currency": 1,
  "notification_type": 1,
  "target": "https://no-reply.originstamp.com/callback"
# currency
  • 0: Bitcoin
  • 1: Ethereum
  • 100: Südkurier
# notification_type
  • 0: Mail
  • 1: Webhook
# target

Mail address or URL to which the notification should be sent.

# url (optional)

This optional parameter which can be used for a preprint URL.

You can generate a UUID-4 beforehand and include it into your document. When submitting your file, the URL is part of the hash, which finally means the link to the timestamp is part of the timestamp itself.

# Response

  "data": {
    "comment": "string",
    "created": false,
    "date_created": 0,
    "hash_string": "string",
    "timestamps": [
        "seed_id": "string",
        "currency_id": 0,
        "private_key": "string",
        "submit_status": 0,
        "timestamp": 0,
        "transaction": "string"
  "error_code": 0,
  "error_message": "string"

This response object is identical in structure to the timestamp status response. Explanations of the individual fields can be found below.

# created

If true, this was the first time the hash was submitted to OriginStamp.