Grok 4.3 vs Step 3.5 Flash
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 Grok 4.3 and Step 3.5 Flash.
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...
Step 3.5 Flash
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token....
Technical Specifications
| Specification | Grok 4.3 | Step 3.5 Flash |
|---|---|---|
| Provider | xAI | StepFun |
| Context Window | 1,000,000 tokens | 262,144 tokens |
| Agent Suitability | 87/100 | N/A |
| Time to First Token (TTFT) | 400 ms | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | stable | stable |
| API Available | Yes | Yes |
| Released Date | 2026-04-30 | 2026-01-29 |
API Pricing Comparison
Input Price per Million Tokens
Grok 4.3
$1.25
Step 3.5 Flash
$0.10
Output Price per Million Tokens
Grok 4.3
$2.50
Step 3.5 Flash
$0.30
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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.
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
Step 3.5 Flash Quirks & Gotchas
No developer gotchas reported.