GPT-5 Nano
OpenAIReleased Aug 7, 2025
GPT-5-Nano is the smallest and fastest variant in the GPT-5 system, optimized for developer tools, rapid interactions, and ultra-low latency environments. While limited in reasoning depth compared to its larger...
- Context window
- 400K tokens
- Input
- text, image, file
- Output
- text
- Tokenizer
- GPT
- Knowledge cutoff
- May 31, 2024
- Released
- Aug 7, 2025
- Reasoning
- always on
Pricing
Per 1M tokens. The provider price and our flat 3% fee are separate columns — what you pay is their sum.
| Per 1M tokens | Provider | + 3% fee | You pay |
|---|---|---|---|
| Input | $0.050 | $0.0015 | $0.052 |
| Output | $0.400 | $0.012 | $0.412 |
| Cache read | $0.010 | $0.0003 | $0.010 |
Benchmarks
Design Arena
| Category | Elo | Win rate | Rank |
|---|---|---|---|
| 3Dmodels | 1041 | 36.1% | #86 |
| Codemodels | 1134 | 48.1% | #74 |
| Data vizmodels | 1104 | 46.7% | #76 |
| Game devmodels | 1111 | 46.6% | #76 |
| UI componentsmodels | 1122 | 52% | #70 |
| Websitesmodels | 1144 | 48.9% | #74 |
Head-to-head preference voting. How we filter and rank
Supported parameters
- include_reasoning
- max_completion_tokens
- max_tokens
- reasoning
- response_format
- seed
- structured_outputs
- tool_choice
- tools
Call it
OpenAI-compatible: point your SDK at api.openkey.ai/v1 and use model openai/gpt-5-nano.
curl https://api.openkey.ai/v1/chat/completions \
-H "Authorization: Bearer $OPENKEY_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "openai/gpt-5-nano",
"messages": [{"role": "user", "content": "Hello"}]
}'import os
from openai import OpenAI
client = OpenAI(
base_url="https://api.openkey.ai/v1",
api_key=os.environ["OPENKEY_API_KEY"],
)
completion = client.chat.completions.create(
model="openai/gpt-5-nano",
messages=[{"role": "user", "content": "Hello"}],
)
print(completion.choices[0].message.content)import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://api.openkey.ai/v1",
apiKey: process.env.OPENKEY_API_KEY,
});
const completion = await client.chat.completions.create({
model: "openai/gpt-5-nano",
messages: [{ role: "user", content: "Hello" }],
});
console.log(completion.choices[0].message.content);Questions
- How much does GPT-5 Nano cost via API?
- Through OpenKey, GPT-5 Nano costs $0.052 per 1M input tokens and $0.412 per 1M output tokens. That is the provider price ($0.050 / $0.400) plus a flat 3% fee — nothing else.
- What is GPT-5 Nano's context window?
- GPT-5 Nano accepts up to 400K tokens of context.
- Is GPT-5 Nano OpenAI-compatible?
- Yes. Send requests to OpenKey's /v1/chat/completions endpoint with model "openai/gpt-5-nano" using any OpenAI SDK — only the base URL and API key change.
- What inputs does GPT-5 Nano support?
- GPT-5 Nano accepts text, image, file input and produces text output. Its knowledge cutoff is May 31, 2024.
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