Using gpt-oss-20b on Vercel AI Gateway

Implementation guide · GPT-OSS · OpenAI

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Vercel AI Gateway exposes gpt-oss-20b through model ID openai/gpt-oss-20b. Use the setup steps, sourced pricing, capabilities, and official provider links below to validate this route before deployment.

Last refreshed 2026-06-29. Next refresh: weekly.

Quick Start

  1. 1
    Create an account at Vercel AI Gateway and generate an API key.
  2. 2
    Use the Vercel AI Gateway SDK or REST API to call openai/gpt-oss-20b — see the documentation for request format.
  3. 3
    You'll be billed $0.05/1M input, $0.20/1M output tokens. See full pricing.

Code Examples

Install
pip install openai
API key
AI_GATEWAY_API_KEY
Model ID
openai/gpt-oss-20b

creator/model-name e.g. kwaipilot/kat-coder-pro-v2

import os
from openai import OpenAI

client = OpenAI(
    api_key=os.environ["AI_GATEWAY_API_KEY"],
    base_url="https://ai-gateway.vercel.sh/v1"
)
response = client.chat.completions.create(
    model="openai/gpt-oss-20b",
    messages=[{"role": "user", "content": "Hello"}]
)
print(response.choices[0].message.content)

Pricing on Vercel AI Gateway

TypePrice (per 1M)
Input tokens$0.05
Output tokens$0.20

Capabilities

JSON / Tool useStructured Outputs

About gpt-oss-20b

OpenAI open-weight model with 20 billion parameters. Lightweight, efficient text-only model with reasoning and function calling. Free for self-hosting. Released August 5, 2025.

Model Specs

Released2025-08-05
Parameters20B
Context131k
ArchitectureDecoder Only
Knowledge cutoff2025-08

Provider

Vercel AI Gateway

Vercel