GPT OSS 120B Turbo API

Fast open-weight reasoning model for affordable analysis, planning, and general-purpose coding help.

Provider: OpenAI | Model ID: gpt-oss-120b-turbo | Context Window: 131K tokens

On this model: 131K tokens context window, reasoning workload class, routed through OpenAI infrastructure.

Pricing

₹20/1M input · ₹90/1M output. Pay-as-you-go micro-metered billing. UPI and cards accepted with zero minimum commitment.

Token TypePrice (INR)
Input Tokens₹20/1M tokens
Output Tokens₹90/1M tokens
Prompt Caching InputStandard input rate

OpenAI-Compatible Integration

Drop into existing OpenAI SDK code by changing the base URL to https://api.luminoai.co.in/v1. The request shape below is the reasoning pattern.

curl https://api.luminoai.co.in/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $LUMINO_API_KEY" \
  -d '{
    "model": "gpt-oss-120b-turbo",
    "messages": [
      {"role": "system", "content": "You are a helpful assistant."},
      {"role": "user", "content": "Work through this problem step by step and give the final answer."}
    ]
  }'

Good fit for reasoning

  • Problems that need multi-step reasoning before the answer
  • Maths, logic, and analysis where a wrong first attempt is costly
  • Planning tasks where the model must weigh several options
  • Evaluation and review work that needs justification, not just output

Model Specifications

Model Identifiergpt-oss-120b-turbo
ProviderOpenAI
Categoryreasoning
Context Window131K tokens
Output Pricing Tierbudget
API ProtocolOpenAI-compatible REST API (JSON)
Endpointhttps://api.luminoai.co.in/v1/chat/completions

Why reasoning models bill more than they appear to

Reasoning models generate hidden reasoning tokens before the visible answer, so the output count you see is not the output count you pay for. Long chains also mean higher latency. Budget for output tokens two to three times the visible answer length.

GPT OSS 120B Turbo API FAQ

Why is GPT OSS 120B Turbo slower than a chat model?

It produces reasoning tokens before the final answer. That extra generation is billed and adds latency.

Can I see the reasoning?

The visible answer is what the API returns by default. Check the model catalog entry for reasoning-trace support on this specific model.

When should I not use a reasoning model?

For short factual replies, classification, and formatting tasks. A cheaper chat tier returns the same result for a fraction of the output cost.

Explore all models in catalog | API Documentation | Test GPT OSS 120B Turbo in Playground