tRNG.info

Quick Start

Generate a random integer between 1 and 100:

fetch('https://api.trng.info/random/int?min=1&max=100')
  .then(response => response.json())
  .then(data => console.log(data.value));

curl "https://api.trng.info/random/int?min=1&max=100"

Base URL

https://api.trng.info

All endpoints are accessed via GET requests over HTTPS. Responses are returned in JSON format.

Authentication

Basic usage requires no authentication. For higher rate limits, request a free API key.

API keys can be passed in two ways:

Header (Recommended)

X-API-Key: your-api-key-here

URL Parameter

https://api.trng.info/random/int?min=1&max=100&api_key=your-api-key-here

To request an API key, contact info@trng.info.

Rate Limits

Rate limit information is included in response headers:

• X-RateLimit-Limit — Maximum requests allowed
• X-RateLimit-Remaining — Requests remaining in current window
• X-RateLimit-Reset — Unix timestamp when the limit resets

Exceeding the rate limit returns HTTP 429 Too Many Requests.

Endpoints

{"value": 42}

{"value": 0.7284653829}

{"bit": 1}

{"value": true}

{"data": "a3f5c8d2e1b4f6a9..."}

{"choice": "B", "index": 1}

{"shuffled": ["C", "A", "D", "B"]}

{"sample": ["C", "A"]}

Error Handling

The API uses standard HTTP status codes. Errors return a JSON body with details:

{"error": "Bad Request", "message": "Parameter 'min' must be less than 'max'"}

Code Examples

Python

import requests

API_BASE = "https://api.trng.info"

# Random integer (1-100)
response = requests.get(
    f"{API_BASE}/random/int",
    params={'min': 1, 'max': 100}
)
print(response.json()['value'])  # 42

# Random choice from list
response = requests.get(
    f"{API_BASE}/random/choice",
    params={'choices': ['red', 'blue', 'green']}
)
print(response.json()['choice'])  # 'blue'

# Random bytes for cryptography (32 bytes = 256 bits)
response = requests.get(
    f"{API_BASE}/random/bytes",
    params={'length': 32}
)
secure_token = response.json()['data']
print(secure_token)  # 'a3f5c8d2e1b4f6a9...'

JavaScript (Node.js / Browser)

const API_BASE = "https://api.trng.info";

// Random float (0-1)
const res1 = await fetch(`${API_BASE}/random/float?min=0&max=1`);
const data1 = await res1.json();
console.log(data1.value);  // 0.7284653829

// Shuffle a list
const res2 = await fetch(
  `${API_BASE}/random/shuffle?items=A&items=B&items=C`
);
const data2 = await res2.json();
console.log(data2.shuffled);  // ['C', 'A', 'B']

// Error handling
try {
  const res = await fetch(`${API_BASE}/random/int?min=1&max=100`);
  if (!res.ok) throw new Error(`HTTP ${res.status}`);
  const data = await res.json();
  console.log(data.value);
} catch (error) {
  console.error('API Error:', error);
}

R

library(httr)
library(jsonlite)

API_BASE <- "https://api.trng.info"

# Random integer
response <- GET(
  paste0(API_BASE, "/random/int"),
  query = list(min = 1, max = 100)
)
content(response)$value  # 42

# Random sample (without replacement)
response <- GET(
  paste0(API_BASE, "/random/sample"),
  query = list(
    items = c("A", "B", "C", "D", "E"),
    count = 3
  )
)
content(response)$sample  # ["C", "A", "E"]

cURL

# Random integer
curl "https://api.trng.info/random/int?min=1&max=100"

# Random boolean
curl "https://api.trng.info/random/bool"

# Random bytes (16 bytes in hex)
curl "https://api.trng.info/random/bytes?length=16"

# With API key
curl -H "X-API-Key: your-key" "https://api.trng.info/random/int?min=1&max=100"

jsPsych (Stimulus Randomization)

// Shuffle trial stimuli using TRNG before starting a jsPsych experiment
const stimuli = ['img/face1.png', 'img/face2.png', 'img/face3.png',
                 'img/scene1.png', 'img/scene2.png', 'img/scene3.png'];

const res = await fetch(
  'https://api.trng.info/random/shuffle?'
  + stimuli.map(s => 'items=' + encodeURIComponent(s)).join('&')
);
const { shuffled } = await res.json();

// Build jsPsych timeline with TRNG-shuffled order
const trials = shuffled.map(img => ({
  type: jsPsychImageKeyboardResponse,
  stimulus: img,
  choices: ['f', 'j'],
  prompt: '<p>Face (F) or Scene (J)?</p>'
}));

jsPsych.run([...trials]);

Secure Token Generation (Python)

import requests

# Generate 32-byte secure token for API key
response = requests.get(
    'https://api.trng.info/random/bytes',
    params={'length': 32}
)
secure_token = response.json()['data']
# Use for API key, session ID, etc.

Support

For API key requests, bug reports, or questions, contact us at info@trng.info.