GPT-OSS 120B vs Claude Sonnet 4.6
Detailed comparison between GPT-OSS 120B and Claude Sonnet 4.6 for RAG applications. See which LLM best meets your accuracy, performance, and cost needs. If you want to compare these models on your data, try Agentset.
Model Comparison
Claude Sonnet 4.6 takes the lead.
Both GPT-OSS 120B and Claude Sonnet 4.6 are powerful language models designed for RAG applications. However, their performance characteristics differ in important ways.
Why Claude Sonnet 4.6:
- Claude Sonnet 4.6 has 496 higher ELO rating
- Claude Sonnet 4.6 delivers better overall quality (4.96 vs 4.83)
- Claude Sonnet 4.6 is 1.8s faster on average
- Claude Sonnet 4.6 has a 53.4% higher win rate
Overview
Key metrics
ELO Rating
Overall ranking quality
GPT-OSS 120B
Claude Sonnet 4.6
Win Rate
Head-to-head performance
GPT-OSS 120B
Claude Sonnet 4.6
Quality Score
Overall quality metric
GPT-OSS 120B
Claude Sonnet 4.6
Average Latency
Response time
GPT-OSS 120B
Claude Sonnet 4.6
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Visual Performance Analysis
Performance
ELO Rating Comparison
Win/Loss/Tie Breakdown
Quality Across Datasets (Overall Score)
Latency Distribution (ms)
Breakdown
How the models stack up
| Metric | GPT-OSS 120B | Claude Sonnet 4.6 | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1242 | 1738 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 14.2% | 67.6% | Percentage of comparisons won against other models |
| Quality Score | 4.83 | 4.96 | Average quality across all RAG metrics |
| Pricing & Context | |||
| Input Price per 1M | $0.04 | $3.00 | Cost per million input tokens |
| Output Price per 1M | $0.19 | $15.00 | Cost per million output tokens |
| Context Window | 131K | 200K | Maximum context window size |
| Release Date | 2025-08-05 | 2026-02-17 | Model release date |
| Performance Metrics | |||
| Avg Latency | 11.3s | 9.5s | Average response time across all datasets |
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import { Agentset } from "agentset";
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const ns = agentset.namespace("ns_1234");
const results = await ns.search(
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);
for (const result of results) {
console.log(result.text);
}Dataset Performance
By benchmark
Comprehensive comparison of RAG quality metrics (correctness, faithfulness, grounding, relevance, completeness) and latency for each benchmark dataset.
MSMARCO
| Metric | GPT-OSS 120B | Claude Sonnet 4.6 | Description |
|---|---|---|---|
| Quality Metrics | |||
| Correctness | 4.93 | 4.97 | Factual accuracy of responses |
| Faithfulness | 4.93 | 4.97 | Adherence to source material |
| Grounding | 4.93 | 4.97 | Citations and context usage |
| Relevance | 4.97 | 5.00 | Query alignment and focus |
| Completeness | 4.80 | 4.97 | Coverage of all aspects |
| Overall | 4.91 | 4.98 | Average across all metrics |
| Latency Metrics | |||
| Mean | 5616ms | 5785ms | Average response time |
| Min | 1255ms | 2066ms | Fastest response time |
| Max | 20330ms | 8195ms | Slowest response time |
PG
| Metric | GPT-OSS 120B | Claude Sonnet 4.6 | Description |
|---|---|---|---|
| Quality Metrics | |||
| Correctness | 4.87 | 5.00 | Factual accuracy of responses |
| Faithfulness | 4.87 | 5.00 | Adherence to source material |
| Grounding | 4.87 | 5.00 | Citations and context usage |
| Relevance | 4.90 | 5.00 | Query alignment and focus |
| Completeness | 4.83 | 5.00 | Coverage of all aspects |
| Overall | 4.87 | 5.00 | Average across all metrics |
| Latency Metrics | |||
| Mean | 19128ms | 12740ms | Average response time |
| Min | 1317ms | 8720ms | Fastest response time |
| Max | 69491ms | 20930ms | Slowest response time |
SciFact
| Metric | GPT-OSS 120B | Claude Sonnet 4.6 | Description |
|---|---|---|---|
| Quality Metrics | |||
| Correctness | 4.70 | 4.87 | Factual accuracy of responses |
| Faithfulness | 4.80 | 4.87 | Adherence to source material |
| Grounding | 4.80 | 4.87 | Citations and context usage |
| Relevance | 4.73 | 5.00 | Query alignment and focus |
| Completeness | 4.57 | 4.83 | Coverage of all aspects |
| Overall | 4.72 | 4.89 | Average across all metrics |
| Latency Metrics | |||
| Mean | 9160ms | 9969ms | Average response time |
| Min | 1606ms | 2886ms | Fastest response time |
| Max | 35709ms | 19276ms | Slowest response time |
Explore More
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