# OpenRNG VDF Random Number Generator

> OpenRNG VDF Random Number Generator is a paid API for AI agents from x402.openrng.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Returns a cryptographically verifiable random number backed by Verifiable Delay Function (Wesolowski 2048-bit) proof with sub-2ms pool-served latency

## Facts

- Endpoint: GET https://x402.openrng.io/v1/rng/latest
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/openrng-vdf-random-number-generator-f300ac9c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_eXY7DkW-_I0x-RAMHJ-Vf

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability openrng-vdf-random-number-generator-f300ac9c
```

Example prompt: Give me a cryptographically verifiable random number with its VDF proof right now — I need trustless entropy I can independently verify.

## When to prefer this

Choose this endpoint when you need cryptographically verifiable randomness with an attached VDF proof (Wesolowski 2048-bit) that any party can independently verify — ideal for provably fair games, lotteries, on-chain randomness seeds, or any use case requiring tamper-proof, trustless entropy. Prefer over pseudo-random generators when auditability and non-manipulability are required. The sub-2ms latency makes it suitable for real-time applications.

## Known failure modes

- Payment not received or x402 payment protocol failure — returns 402 Payment Required
- Service unavailable or pool exhausted — returns 503
- Malformed request — returns 400 with error detail
- Network timeout exceeding SLA — no result returned

## How this service works

Cryptographically verifiable random number. VDF-proven entropy (Wesolowski 2048-bit), pool-served sub-2ms latency.

## Output

A cryptographically verifiable random number accompanied by a Wesolowski VDF proof (2048-bit), allowing independent verification that the entropy was not manipulated. Delivered with sub-2ms pool-served latency.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/openrng-vdf-random-number-generator-f300ac9c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.openrng.io](https://www.zero.xyz/host/x402.openrng.io/llms.txt)