# GPT 5 Nano

GPT 5 Nano is a reasoning model by OpenAI with vision, function calling, web search, prompt caching, structured output — designed for complex, multi-step problem solving where accuracy matters more than speed. It supports a 272K token context window with up to 128K tokens of output. Priced at $0.05 per million input tokens and $0.4 per million output tokens, it is one of the most cost-efficient options in its class. Access GPT 5 Nano through [Inworld Router](https://platform.inworld.ai/routers) with OpenAI SDK compatibility, built-in failover, and intelligent routing across providers.

→ Function Calling Web Search Reasoning Prompt Caching Response Schema Vision reasoning Capability

## Step 1 — Create Router

### cURL

```bash
curl --location 'https://api.inworld.ai/router/v1/routers' \
--header 'Authorization: Basic <your-api-key>' \
--header 'Content-Type: application/json' \
--data '{
  "name": "compare-frontier-models",
  "defaultRoute": {
    "route_id": "default",
    "variants": [
      {
        "variant": {
          "variant_id": "openai/gpt-5-nano-a",
          "model_id": "openai/gpt-5-nano"
        },
        "weight": 33
      },
      {
        "variant": {
          "variant_id": "openai/gpt-3.5-turbo-b",
          "model_id": "openai/gpt-3.5-turbo"
        },
        "weight": 33
      },
      {
        "variant": {
          "variant_id": "openai/gpt-4.1-c",
          "model_id": "openai/gpt-4.1"
        },
        "weight": 34
      }
    ]
  }
}'
```

### Python

```python
import requests

response = requests.post(
    "https://api.inworld.ai/router/v1/routers",
    headers={
        "Authorization": "Basic <your-api-key>",
        "Content-Type": "application/json",
    },
    json={
        "name": "compare-frontier-models",
        "defaultRoute": {
            "route_id": "default",
            "variants": [
                {
                    "variant": {
                        "variant_id": "openai/gpt-5-nano-a",
                        "model_id": "openai/gpt-5-nano"
                    },
                    "weight": 33
                },
                {
                    "variant": {
                        "variant_id": "openai/gpt-3.5-turbo-b",
                        "model_id": "openai/gpt-3.5-turbo"
                    },
                    "weight": 33
                },
                {
                    "variant": {
                        "variant_id": "openai/gpt-4.1-c",
                        "model_id": "openai/gpt-4.1"
                    },
                    "weight": 34
                }
            ]
        }
    },
)
print(response.json())
```

### JavaScript

```javascript
const response = await fetch(
"https://api.inworld.ai/router/v1/routers",
{
    method: "POST",
    headers: {
      Authorization: "Basic <your-api-key>",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      name: "compare-frontier-models",
      defaultRoute: {
        route_id: "default",
        variants: [
          {
            variant: {
              variant_id: "openai/gpt-5-nano-a",
              model_id: "openai/gpt-5-nano",
            },
            weight: 33,
          },
          {
            variant: {
              variant_id: "openai/gpt-3.5-turbo-b",
              model_id: "openai/gpt-3.5-turbo",
            },
            weight: 33,
          },
          {
            variant: {
              variant_id: "openai/gpt-4.1-c",
              model_id: "openai/gpt-4.1",
            },
            weight: 34,
          },
        ],
      },
    }),
}
);
const data = await response.json();
console.log(data);
```

## Step 2 — Chat Completion

### cURL

```bash
curl --location 'https://api.inworld.ai/v1/chat/completions' \
--header 'Authorization: Basic <your-api-key>' \
--header 'Content-Type: application/json' \
--data '{
  "model": "inworld/compare-frontier-models",
  "messages": [{"role": "user", "content": "Hello!"}]
}'
```

### Python

```python
from openai import OpenAI

client = OpenAI(
    api_key="<your-api-key>",
    base_url="https://api.inworld.ai/v1",
)

response = client.chat.completions.create(
    model="inworld/compare-frontier-models",
    messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)
```

### JavaScript

```javascript
import OpenAI from "openai";

const client = new OpenAI({
    apiKey: "<your-api-key>",
    baseURL: "https://api.inworld.ai/v1",
});

const response = await client.chat.completions.create({
    model: "inworld/compare-frontier-models",
    messages: [{ role: "user", content: "Hello!" }],
});
console.log(response.choices[0].message.content);
```

## GPT 5 Nano pricing and providers

Access GPT 5 Nano through OpenAI via [Inworld Router](https://platform.inworld.ai/routers) or Realtime API. By using the AI provider(s) below you acknowledge you reviewed and agree to their terms listed in the Legal section under the AI provider's name.

| Provider | Context | Max Output | Input ($/1M tokens) | Output ($/1M tokens) | Capabilities | Input modalities | Output modalities |
| --- | --- | --- | --- | --- | --- | --- | --- |
| OpenAI | 272K | 128K | $0.05 | $0.40 | +4 |  |  |

## Other OpenAI models available through Inworld

Compare GPT 5 Nano with other OpenAI models available through [Inworld Router](https://platform.inworld.ai/routers) or Realtime API.

| Model | Context | Max Output | Input ($/1M tokens) | Output ($/1M tokens) | Capabilities | Input modalities | Output modalities | Inference provider |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| [GPT 3.5 Turbo](/content/models/openai-gpt-3-5-turbo/index.html) | 16.4K | 4.1K | $0.50 | $1.50 |  |  |  | OpenAI |
| [GPT 4.1](/content/models/openai-gpt-4-1/index.html) | 1M | 32.8K | $2.00 | $8.00 | +2 |  |  | OpenAI |
| [GPT 4.1 Mini](/content/models/openai-gpt-4-1-mini/index.html) | 1M | 32.8K | $0.40 | $1.60 | +2 |  |  | OpenAI |
| [GPT 4.1 Nano](/content/models/openai-gpt-4-1-nano/index.html) | 1M | 32.8K | $0.10 | $0.40 | +1 |  |  | OpenAI |
| [GPT 4o](/content/models/openai-gpt-4o/index.html) | 128K | 16.4K | $2.50 | $10.00 | +1 |  |  | OpenAI |
| [GPT 5 Mini](/content/models/openai-gpt-5-mini/index.html) | 272K | 128K | $0.25 | $2.00 | +4 |  |  | OpenAI |
| [Openai/gpt Oss 120b](/content/models/deepinfra-openai-gpt-oss-120b/index.html) | 131.1K | 131.1K | $0.039 | $0.19 | +2 |  |  | DeepInfra |

## Start building with GPT 5 Nano

Access GPT 5 Nano and every other model through Inworld Router or Realtime API. Create your free account and start routing in minutes.

[Get Started Free](https://platform.inworld.ai/routers) [Contact Sales](/content/contact-sales/index.html)