GPT-5 vs gpt-oss-120b
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for GPT-5 and gpt-oss-120b.
GPT-5
GPT-5 is OpenAI’s most advanced model, offering major improvements in reasoning, code quality, and user experience. It is optimized for complex tasks that require step-by-step reasoning, instruction following, and accuracy...
gpt-oss-120b
gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI designed for high-reasoning, agentic, and general-purpose production use cases. It activates 5.1B parameters per forward pass and is optimized...
Technical Specifications
| Specification | GPT-5 | gpt-oss-120b |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Context Window | 400,000 tokens | 131,072 tokens |
| Agent Suitability | 92/100 | N/A |
| Time to First Token (TTFT) | 320 ms | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | stable | stable |
| API Available | Yes | Yes |
| Released Date | 2025-08-07 | 2025-08-05 |
API Pricing Comparison
Input Price per Million Tokens
GPT-5
$1.25
gpt-oss-120b
$0.03
Output Price per Million Tokens
GPT-5
$10.00
gpt-oss-120b
$0.15
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
GPT-5 Quirks & Gotchas
- ▸Reliable all-rounder — use as default for most production workflows
- ▸Not recommended for advanced reasoning chains — use o3-mini instead
gpt-oss-120b Quirks & Gotchas
No developer gotchas reported.