Compare · updated 2026-11-01

Claude Opus vs Kimi K3.1 Pro

Claude Opus is better at writing, coding, reasoning, maths, translation; Kimi K3.1 Pro is better at quick answers, structured data, long documents. Kimi K3.1 Pro is the cheaper of the two on output.

Measured quality by task

TaskClaude OpusKimi K3.1 ProBetter
Quick answers82/10091/100Kimi K3.1 Pro
Writing94/10092/100Claude Opus
Coding98/10089/100Claude Opus
Reasoning99/10085/100Claude Opus
Maths96/10081/100Claude Opus
Structured data87/10092/100Kimi K3.1 Pro
Long documents87/10090/100Kimi K3.1 Pro
Translation92/10091/100Claude Opus

Quality is Nivana’s measured score for each kind of task, from weekly pairwise evals judged by models from several labs. Prices are live AI Gateway list prices per million tokens. Updated 2026-11-01. How this is measured.

Price and context

Claude OpusKimi K3.1 Pro
LabAnthropicMoonshot
Input per 1M tokens$4$2
Output per 1M tokens$20$10
Typical chat answer$0.020$0.010
Context window1M1.05M
Router picks it for3 of 24 request typesFallback only

Which should you use?

Use the one that wins the kind of work you do most, unless the price gap outweighs the quality gap for easy requests. Or don’t choose: Nivana scores both, and the rest of the pool, on every request and sends it to whichever is best for that request.

Questions

Is Claude Opus better than Kimi K3.1 Pro?

On Nivana’s weekly evals Claude Opus scores higher on 5 of 8 task types (writing, coding, reasoning, maths, translation) and Kimi K3.1 Pro on 3 (quick answers, structured data, long documents). Neither is better at everything.

Which is better for coding, Claude Opus or Kimi K3.1 Pro?

Claude Opus: 98/100 against 89/100 for Kimi K3.1 Pro on Nivana’s coding evals.

Which is better for writing, Claude Opus or Kimi K3.1 Pro?

Claude Opus: 94/100 against 92/100 for Kimi K3.1 Pro on Nivana’s writing evals.

Which is cheaper, Claude Opus or Kimi K3.1 Pro?

Kimi K3.1 Pro: $10 per million output tokens against $20 for Claude Opus, about 2.0× less. A typical chat answer costs about $0.010 on Kimi K3.1 Pro and $0.020 on Claude Opus.

Or let the router pick, per request

Nivana sends every message to the model that scores best for it, sets how hard it thinks, and tells you which one answered. 2,000 free credits to start, no card.