Compare AI models
| Specifications | ||
ParametersThe learned values that shape how a model responds. B means billion and T means trillion. For mixture-of-experts models, the total count is larger than the number active for each token. Parameter count alone does not measure quality. | — | 72B |
Context windowHow much information the model can work with in one request, measured in tokens — pieces of words or other data. This includes your question, attachments, conversation and reply. Limits can vary by model variant and provider. | 200k | 128k |
| API pricingUSD per 1M tokens · lower wins | ||
Cheapest inputLowest input rate across every provider on OpenRouter, the lab included. The cheapest endpoint may run a quantised build or a shorter context — see "Available from" on the model page. | $15.00Amazon Bedrock | — |
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input. | $75.00Amazon Bedrock | — |
| $6,750Amazon Bedrock | — | |
| Benchmarks | ||
SWE-Bench VerifiedCoding — Real coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | 74.5% | 60.4% |
BullshitBench v2Nonsense detection — Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | 43% | — |
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 80.9% | — |
| Overview | ||
| Company | Anthropic | Moonshot AI |
| Release date | Aug 5 2025 | Jun 17 2025 |
| Access | Closed | Open Weight |
| Model details | View model | View model |
Other comparisons
Claude Opus 4.1vsGPT-6.1 SolKimi-DevvsGPT-6.1 SolClaude Opus 4.1vsGemini 4 ArgonKimi-DevvsGemini 4 ArgonClaude Opus 4.1vsMuse Spark OpenKimi-DevvsMuse Spark OpenClaude Opus 4.1vsGrok 4.7Kimi-DevvsGrok 4.7Claude Opus 4.1vsDeepSeek-V4.1-Flash-1017Kimi-DevvsDeepSeek-V4.1-Flash-1017Claude Opus 4.1vsMistral Large 4Kimi-DevvsMistral Large 4Frequently asked questions
Claude Opus 4.1 leads Kimi-Dev on 1 of the 1 benchmark they both report (SWE-Bench Verified). Kimi-Dev shipped 49 days before Claude Opus 4.1, so benchmark comparisons should account for the intervening progress.
Context windows are 200k (Claude Opus 4.1) vs 128k (Kimi-Dev). Claude Opus 4.1 is closed, while Kimi-Dev is open weight.
On SWE-Bench Verified, Claude Opus 4.1 leads at 74.5% vs Kimi-Dev at 60.4%.