gpt-oss-20b
OpenAI gpt-oss-20b — pricing, 131k context window, API cost calculator and alternatives.
By OpenAI
Specs
- Provider
- OpenAI
- Slug
- openai/gpt-oss-20b
- Capabilities
- tools, json_mode
Pricing freshness
- Tier
- standard
- Currency
- USD
- As of
- 2026-05-08 17:08 UTC
Pricing history
Tracking gpt-oss-20b pricing since 2026-05-08. We'll plot the chart here once it changes.
Quickstart — call gpt-oss-20b from your app
curl https://api.openai.com/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $OPENAI_API_KEY" \
-d '{
"model": "gpt-oss-20b",
"messages": [{"role": "user", "content": "Hello!"}]
}'Official docs: https://platform.openai.com/docs/api-reference/chat
# pip install openai
from openai import OpenAI
client = OpenAI(
base_url="https://api.openai.com/v1",
api_key=os.environ["OPENAI_API_KEY"],
)
resp = client.chat.completions.create(
model="gpt-oss-20b",
messages=[{"role": "user", "content": "Hello!"}],
)
print(resp.choices[0].message.content)Official docs: https://platform.openai.com/docs/api-reference/chat
// npm install openai
import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://api.openai.com/v1",
apiKey: process.env.OPENAI_API_KEY,
});
const resp = await client.chat.completions.create({
model: "gpt-oss-20b",
messages: [{ role: "user", content: "Hello!" }],
});
console.log(resp.choices[0].message.content);Official docs: https://platform.openai.com/docs/api-reference/chat
Related models
Similar capabilities, context window, and price tier — drawn from across the catalog so you can compare alternatives in one click.
Frequently asked questions
What is gpt-oss-20b?
gpt-oss-20b is a large language model API from OpenAI with a 131k-token context window. It costs $0.03 per 1M input tokens and $0.14 per 1M output tokens.
How much does gpt-oss-20b cost?
gpt-oss-20b is priced at $0.03 per 1M input tokens and $0.14 per 1M output tokens via the OpenAI API. A 50/50 input/output workload of 1M total tokens costs about $0.085.
What is the context window of gpt-oss-20b?
gpt-oss-20b supports up to 131k tokens of context per request — roughly 262 pages of English text or 16384 lines of code at a typical density.
Does gpt-oss-20b support vision, tool use, or JSON mode?
gpt-oss-20b supports tool/function calling and structured JSON mode. It does not support image input (vision).
Who makes gpt-oss-20b?
gpt-oss-20b is built and operated by OpenAI. Pricing, context window, and capabilities on this page are refreshed nightly from OpenAI's public catalog.
Can I self-host gpt-oss-20b?
gpt-oss-20b is API-only — its weights are not publicly distributed by OpenAI, so it cannot be self-hosted today.