gpt-oss-20b vs Grok 4.3
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-oss-20b and Grok 4.3.
gpt-oss-20b
gpt-oss-20b is an open-weight 21B parameter model released by OpenAI under the Apache 2.0 license. It uses a Mixture-of-Experts (MoE) architecture with 3.6B active parameters per forward pass, optimized for...
Grok 4.3
Grok 4.3 is a reasoning model from xAI. It accepts text and image inputs with text output, and is suited for agentic workflows, instruction-following tasks, and applications requiring high factual...
Technical Specifications
| Specification | gpt-oss-20b | Grok 4.3 |
|---|---|---|
| Provider | OpenAI | xAI |
| Context Window | 131,072 tokens | 1,000,000 tokens |
| Agent Suitability | N/A | 87/100 |
| Time to First Token (TTFT) | N/A | 400 ms |
| Deployment Model | managed api | managed api |
| Production Stability | stable | stable |
| API Available | Yes | Yes |
| Released Date | 2025-08-05 | 2026-04-30 |
API Pricing Comparison
Input Price per Million Tokens
gpt-oss-20b
$0.03
Grok 4.3
$1.25
Output Price per Million Tokens
gpt-oss-20b
$0.14
Grok 4.3
$2.50
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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-oss-20b Quirks & Gotchas
No developer gotchas reported.
Grok 4.3 Quirks & Gotchas
- ▸Strong coding performance — competitive with Claude Sonnet at similar price point
- ▸Upgrade to Grok 4.20 for improved reasoning and tool calling