Claude 3 SonnetvsKimi K2.6
Claude 3 Sonnet | Kimi K2.6 | |
|---|---|---|
| Specifications | ||
ParametersA rough measure of how big the model is. More parameters usually means more capable and more expensive to run, though it is a poor guide on its own — a smaller, newer model often beats a larger, older one. | — | 1T |
Context windowHow much text the model can hold in mind at once — your question, any documents you attach, the conversation so far, and its own reply. Go past it and the earliest part falls out of view. | — | 256k |
| API pricingUSD per 1M tokens · lower wins | ||
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it. | — | $0.95 |
Output priceWhat you pay for the text the model writes back. It is normally the dearer half: producing an answer costs more than reading one. | — | $4.00 |
Cached input priceA reduced rate for text you send over and over. If every request starts with the same instructions or the same document, the provider keeps a copy ready and charges less to read it again. | — | $0.16 |
| Benchmarks | ||
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 40.4% | 90.5% |
| BenchmarksPublished by one model only | ||
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. | — | 65% |
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. | — | 80.2% |
CursorBench v3.1Agentic coding — Cursor's own test of harder, real-world coding tasks inside a code editor. Higher is better. | — | 47.6% |
Next.js EvalsNext.js coding — Vercel's open eval of how well AI coding agents build and migrate real Next.js apps — measured as the share of tasks the agent completes successfully. Higher is better. | — | 67% |
LiveCodeBenchCompetitive coding — Coding problems published so recently the AI can't have seen them in training — a contamination-free test of raw programming skill. Higher is better. | — | 89.6% |
Arena Elo (Text)Community preference — Real people chat with two anonymous AIs side by side and vote for the answer they prefer. Votes become a chess-style Elo rating on arena.ai — it measures which AI people actually like, not test scores. Higher is better. | — | 1461 |
Arena Elo (Code)Community preference (code) — Like the text arena, but people vote on which AI writes better code. The votes become a chess-style Elo rating on arena.ai. Higher is better. | — | 1513 |
| Overview | ||
| Company | Anthropic | Moonshot AI |
| Release date | Mar 4 2024 | Apr 21 2026 |
| Access | Proprietary | Open Weight |
Frequently asked questions
Kimi K2.6 leads Claude 3 Sonnet on 1 of the 1 benchmark they both report (GPQA Diamond). Only Kimi K2.6 has a verified first-party API price: $0.95 per million input tokens and $4.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude 3 Sonnet. Claude 3 Sonnet shipped 778 days before Kimi K2.6, so benchmark comparisons should account for the intervening progress.
Claude 3 Sonnet is proprietary, while Kimi K2.6 is open weight.
On GPQA Diamond, Kimi K2.6 leads at 90.5% vs Claude 3 Sonnet at 40.4%.
Claude 3 Sonnet was released by Anthropic on Mar 4 2024.
Kimi K2.6 was released by Moonshot AI on Apr 21 2026.
Kimi K2.6 leads on GPQA Diamond — Claude 3 Sonnet 40.4% vs Kimi K2.6 90.5%.
Only Kimi K2.6 has a verified first-party API price: $0.95 per million input tokens and $4.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude 3 Sonnet. Rates are pay-as-you-go API prices verified on August 18, 2026.
Claude 3 Sonnet is a proprietary model released by Anthropic. Kimi K2.6 is an open weight model released by Moonshot AI.