Quantum Entropy

Using Qrypt’s Quantum Entropy Service

Qrypt’s Entropy as a Service is a RESTful web service that allows you to generate random data (henceforth referred to as entropy or random) that is truly random—based on quantum-mechanical phenomena.

Getting Started

To start using Qrypt’s Quantum Entropy service you need to create a Qrypt account, obtain an access token, and submit an HTTP request.

Create a free Qrypt account

To request entropy from the service, you must first create an account.

  1. Navigate to https://portal.qrypt.com and create a new account.
  2. Enter your email address and a strong password, then click the button to create your account.
  3. Check your email for the 4-digit account confirmation code and enter it on the website to confirm your account.
  4. When prompted, enter your first and last name.

Generate an access token

An access token is required to submit REST API requests.

  1. Navigate to the Tokens page.
  2. Assign a name to the token to help you distinguish between different tokens.
  3. Select the expiration period. This determines when the token will expire and need to be replaced.
  4. Click the “Generate token” button.
  5. The generated token will be displayed along with an example of how entropy data can be requested. Copy the token using the “Copy” button and store it in a secure location. Important: This is the only time you will be able to view the access token. Be sure to copy and store it before closing this popup.
  6. Save the access token to a secure location. Because your access token is used to make requests for entropy—a budgeted resource—it should be treated as secure data, very much like a password.

Submit a request for entropy

To get entropy from the service, you must submit an HTTP request to the REST API service, providing the aforementioned access token and specifying the number of 1,024-byte blocks of entropy you would like to receive. You must also specify an access token—which identifies the user account requesting the data—in an HTTP “authorization” header. The data is returned in a JSON-encoded structure containing an array of base64-encoded strings, each of which decodes to a 1,024-byte block of entropy, as well as an integer specifying the number of strings in the array.

To ensure the privacy of your access token and the entropy data, all calls are made using an encrypted HTTPS connection.

Follow these steps in your preferred tool or language of choice to request entropy (see subsequent sections Request and Response for details):

  1. Specify your access token and the desired number of kibibytes (1,024 bytes) of entropy in a web request. Use the following URL: https://api-eus.qrypt.com/api/v1/quantum-entropy?size={kib_entropy}.
  2. Replace {kib_entropy} in the aforementioned URL with an integer indicating the number of kibibytes of entropy to return.
  3. Include an HTTP “Accept” header field with a value of “application/json”.
  4. Include an HTTP “Authorization” header with a value of “Bearer {access_token}”, where {access_token} is the access token obtained from the Qrypt portal.
  5. Submit the HTTP request using the HTTP GET method.
  6. If the HTTP request is successful, the JSON-formatted response will contain a structure containing two fields named “random” and “size”. The “random” field contains an array of base64-encoded strings (each of which—when decoded—contains 1,024 bytes of entropy). The “size” field contains the number of elements in the “random” field.

The following sections provide more detailed explanations of the request and response.


The web service consists of one REST API call, which returns the entropy. The following table describes the properties of a valid REST API call.

URL https://api-eus.qrypt.com/api/v1/quantum-entropy?size={kib_entropy}

{kib_entropy} is an integer that specifies the number of kibibytes (1,024 bytes) of entropy being requested. The minimum value is 1 and the maximum value is 512. If unspecified, the default value is one (1).
"Bearer {qrypt_access_token}"

{qrypt_access_token} is an access token generated in the Qrypt portal.

Qrypt’s Quantum Entropy service is hosted in several locations worldwide. This allows you to access a server that is closer to the client for better reliability and response time. The following table (Table 2) indicates which subdomain to use in your URL to access the server located in the specified region.

Subdomain Geographic location
api-eus Eastern United States


The response from the HTTP request will contain a numeric status code indicating whether or not the request succeeded and, if not, why. If successful, it will also return the entropy.

Status code Description
200 Success
Entropy was successfully returned.
400 Bad request
The request was invalid (i.e., malformed or otherwise unacceptable). Please verify the format of the URL and the specified parameters.
401 Unauthorized
The access token is either invalid or has expired.
403 Limit reached
The account associated with the specified access token has already retrieved the maximum allotment of entropy allowed for the current period. Please contact a Qrypt representative to request a change to your limit.
429 Rate Limit reached
The access token used to pull random has exceeded the maximum number of requests (30) allowed for the designated time interval (10 seconds). Please wait and try again.
500 Internal server error
The Qrypt service has encountered an internal error. Please contact Qrypt support for further assistance.
503 Not enough supply
Qrypt’s supply of entropy is temporarily insufficient to fulfill the request. Please wait and try the request again.

If a success status code of 200 was returned, the response contains a JSON-encoded structure containing an array size (which should match the kib_entropy value specified in the request) and an array of base64-encoded strings which, when decoded, contains 1,024 bytes of entropy.

JSON Fields Description
random An array of base64-encoded strings (as defined in RFC 4648 §4, Base 64 Encoding) . The length of the array is specified in the size field (below). Each string, when decoded, contains a 1,024-byte sequence of entropy.
size The number of base64-encoded strings in the array returned in the random field (above).

The following illustrates an example of JSON output as returned by a request for two 1,024-byte blocks of entropy:

"random": [
  "<base64 encoding of 1,024 bytes of entropy>",
  "<base64 encoding of 1,024 bytes of entropy>"
"size": 2


The following examples demonstrate how to submit a request and display the returned entropy. In the following examples, {subdomain} should be replaced with the subdomain for a server in the geographic location you would like to use (see Table 2), {kib_entropy} should be replaced with an integer between 1 and 512, and {qrypt_access_token} should be replaced with an access token generated using your Qrypt account.


The following shows an example of how to submit a request for {kib_entropy} kibibytes of entropy using the {qrypt_access_token} via the curl command-line command. This command can be executed at a Windows or Unix command prompt.

curl https://{subdomain}.qrypt.com/api/v1/quantum-entropy?size={kib_entropy} -H "Authorization: Bearer {qrypt_access_token}"


The following shows an example of how to submit a request for {kib_entropy} kibibytes of data using the {qrypt_access_token} in PowerShell.

Specify entropy token, requested size of entropy, and subdomain

[string] $accesstoken = '{qrypt_access_token}'
[int] $kibData = {kib_entropy}
[string] $sub = '{subdomain}'

Define the request URL

[string] $url = "https://$sub.qrypt.com/api/v1/quantum-entropy?size=$kibData"

Define and submit the request

$response =  Invoke-RestMethod -Method Get -Uri $url -UseBasicParsing `-Headers @{ authorization = "Bearer $accesstoken" } ` -ContentType 'application/json'

Display the entropy bytes

response.random | foreach { [Convert]::FromBase64String($_) }


The following shows an example of how to submit a request for {kib_entropy} kibibytes of data using the {qrypt_access_token} in Python.

You may need to install the “requests” module before executing this example. For example, use the following command:

python -m pip install requests
import requests
import base64

# Specify entropy token, requeststed size of entropy, and subdomain
accesstoken = '{qrypt_access_token}'
kibData = {kib_entropy}
sub = '{subdomain}'

# Define the request URL
url = f'https://{sub}.qrypt.com/api/v1/quantum-entropy'

# Define and submit the request
headers = { 'Authorization': f'Bearer {accesstoken}' }
params = { 'size': kibData }
response = requests.get( url, headers=headers, params=params)

# Display the entropy bytes
for s in response.json()['random']:
    for b in base64.decodebytes( s.encode('ascii') ):
        print( f'{b}')


The following shows an example of how to submit a request for {kib_entropy} kibibytes of data using the {qrypt_access_token} in JavaScript.

"use strict";

// Specify entropy token, requested size of entropy, and subdomain
let accessToken = "{qrypt_access_token}";
let kibData = { kib_entropy };
let sub = "{subdomain}";

// Define the request URL
let url = `https://${sub}.qrypt.com/api/v1/quantum-entropy?size=${kibData}`;

// Submit the request and process the response
fetch(url, {
  method: "GET",
  headers: {
    Accept: "application/json",
    Authorization: "Bearer " + accessToken,
  .then((response) => response.json())
  .then(function (json) {
    // Display the entropy bytes
    json.random.forEach((b64) =>
      [...atob(b64)].forEach((c) => console.log(c.charCodeAt(0)))