Objective comparison based on public benchmarks updated weekly: Intelligence Index, Chatbot Arena ELO, pricing and speed.
Overall winner (2026)
Claude Opus 5.5 (Max, Default Fallback)
3 of 5 criteria won
Anthropic
Intelligence Index
57.6
3 criteria won
View full profile →| Critério | Claude Opus 5.5 (Max, Default Fallback) | Kimi K3.1 Pro |
|---|---|---|
| Chatbot Arena ELO | — | — |
| Intelligence Index (AA) | 57.6 ✓ | 55.1 |
| Coding Index (AA) | — | — |
| Input price ($/1M tok) | $4.00 | $2.00 ✓ |
| Output price ($/1M tok) | $20.00 | $10.00 ✓ |
| Context window | 1.0M tokens ✓ | — |
| Speed (tokens/s) | 98 tok/s ✓ | 41 tok/s |
✓ = winner in this criterion • Source: Artificial Analysis, LMArena, official APIs • Updated weekly
Choosing between Claude Opus 5.5 (Max, Default Fallback) and Kimi K3.1 Pro depends on your use case, budget and technical requirements. Below, a practical guide based on benchmark data and each model's specifications.
Anthropic · Text
Kimi · Text
Claude Opus 5.5 (Max, Default Fallback) wins in 3 of 5 criteria analyzed. Check the full table to choose based on your use case.
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. Kimi K3.1 Pro is cheaper: $2/1M input tokens vs $4/1M tokens for Claude Opus 5.5 (Max, Default Fallback) — a 100% difference. For high-volume projects, Kimi K3.1 Pro can reduce costs substantially.
Claude Opus 5.5 (Max, Default Fallback) has a context window of 1.0M tokens. Context window data for Kimi K3.1 Pro is not publicly available.