Objective comparison based on public benchmarks updated weekly: Intelligence Index, Chatbot Arena ELO, pricing and speed.
| Critério | GPT-5.5 Pro | Grok 4.3 |
|---|---|---|
| Chatbot Arena ELO | — | — |
| Intelligence Index (AA) | 54.8 ✓ | 36.3 |
| Coding Index (AA) | 74.9 ✓ | 69.9 |
| Input price ($/1M tok) | $30.00 | $1.25 ✓ |
| Output price ($/1M tok) | $180.00 | $2.50 ✓ |
| Context window | 1.1M tokens ✓ | 1.0M tokens |
| Speed (tokens/s) | — | 134 tok/s ✓ |
✓ = winner in this criterion • Source: Artificial Analysis, LMArena, official APIs • Updated weekly
Choosing between GPT-5.5 Pro and Grok 4.3 depends on your use case, budget and technical requirements. Below, a practical guide based on benchmark data and each model's specifications.
OpenAI · Multimodal
xAI · Multimodal
GPT-5.5 Pro and Grok 4.3 are evenly matched in this comparison. Choose based on the criterion most important for your project.
Data is aggregated from Artificial Analysis (Intelligence Index, Coding Index) and Chatbot Arena/LMArena (ELO). Pricing and specs come from official APIs. Updated weekly.
The Intelligence Index is an aggregate score from Artificial Analysis that combines multiple academic benchmarks (MMLU, GPQA, LiveBench, etc.) into a single rating. The higher the score, the more capable the model is at reasoning tasks.
No. Grok 4.3 is cheaper: $1.25/1M input tokens vs $30/1M tokens for GPT-5.5 Pro — a 2300% difference. For high-volume projects, Grok 4.3 can reduce costs substantially.
GPT-5.5 Pro has the larger context window: 1.1M tokens vs 1.0M tokens. For long document analysis, extensive transcripts or full codebases, the larger context window is a decisive criterion.