> For the complete documentation index, see [llms.txt](https://docs.nexus.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nexus.xyz/overview/exchange-testnet.md).

# Exchange testnet

Trade the testnet venue: authenticate, mint a key, claim synthetic USDX, and place an order.

The Nexus Exchange is live on testnet at [nexus.xyz/trade](https://nexus.xyz/trade).

You can authenticate through the API, place orders, and trade the live perpetual futures markets.

You can trade in the web terminal (see [Terminal features](/terminal/terminal.md)) or over the REST and WebSocket APIs.

The [API Reference](https://docs.nexus.xyz/api-reference) section of these docs has the full API documentation.

### Getting started

#### 1. Authenticate

Sign in with your Ethereum wallet using an EIP-191 personal signature:

```bash
POST /auth/login
```

Sign the message `"Sign in to Nexus Exchange"` to receive a session token (24-hour TTL). Your first sign-in creates your account.

#### 2. Create an API key

```bash
POST /keys
```

The call returns an HMAC key pair (`key_id` + `secret`). The secret is shown once, so store it immediately.

Manage keys with `GET /keys` (list) and `DELETE /keys/{key_id}` (revoke).

#### 3. Fund your account

Credit your testnet account with synthetic USDX from the faucet:

```bash
POST /account/credit
```

You need a USDX balance before you can place orders. Check your balance at any time with `GET /account`.

**Each API key can claim up to 500 test USDX per day.**

#### 4. Place an order

Authenticate all trading requests with three headers: `X-API-Key`, `X-Timestamp`, `X-Signature`.

```bash
POST /orders
```

```json
{
  "market_id": "BTC-USDX-PERP",
  "side": "Buy",
  "order_type": "Limit",
  "price": "67000",
  "quantity": "0.01",
  "time_in_force": "GTC"
}
```

See the [API Reference](https://docs.nexus.xyz/api-reference) section for complete authentication examples and all available endpoints.

### Markets

Three crypto perpetuals are live, all denominated in USDX:

| Market          | Underlying |
| --------------- | ---------- |
| `BTC-USDX-PERP` | Bitcoin    |
| `ETH-USDX-PERP` | Ether      |
| `SOL-USDX-PERP` | Solana     |

The set changes as markets are listed and delisted. Query `GET /markets` for what is live now, or `GET /markets/summary` for the set with its statistics. See the [Asset directory](/asset-directory/asset-directory.md) for the classes that follow.

### Venue telemetry

Aggregate venue telemetry is available over the API. These endpoints are **public** and need no API key:

| Endpoint                          | What it returns                                        |
| --------------------------------- | ------------------------------------------------------ |
| `GET /stats`                      | Venue snapshot, including rolling unique-trader counts |
| `GET /stats/history`              | Throughput samples over time                           |
| `GET /stats/volume`               | Cumulative traded notional, venue total and per market |
| `GET /stats/open-interest`        | Open interest, long and short reported separately      |
| `GET /stats/balance-distribution` | Accounts per balance band                              |

Each of these is documented as carrying **no per-account data by construction**, which is why they are public. See [Venue Statistics](https://docs.nexus.xyz/api-reference/guides/statistics) for the response shapes and the sign and unit traps. In particular, open interest reports the two sides separately, and `gross_oi_two_sided_quote` is twice the one-sided figure.

The terminal's public [Data](https://nexus.xyz/data) dashboard charts venue volume, open interest and funding. For raw figures, use the endpoints above.


---

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