Grok 4.3 vs Kimi K2.6

Compare Grok 4.3 and Kimi K2.6 on the metrics that decide an agent workload.

MetricGrok 4.3Kimi K2.6
ProviderxAIFireworks AI
Input / 1M$1.25$0.95
Output / 1M$2.50$4.00
Cache read / 1M$0.20 (−84%)$0.16 (−83%)
Reuse-adj @55%$1.13$1.39
Context1M262K
Cache capture76%81%
Warm TTFT280ms (−56%)140ms (−63%)
Quality index9285

Teal marks the better value in each row. Reuse-adjusted assumes 55% prefix reuse and a 25% output share.

Pick Grok 4.3 when

Pick Grok 4.3 when it scores higher on the composite quality index, it is cheaper once prefix reuse is priced in, it carries the larger 1M context window.

Pick Kimi K2.6 when

Pick Kimi K2.6 when it answers faster on warm cache hits, it captures more of the available reuse, it is open-weights for on-prem and regulated lanes.

Verdict

Grok 4.3 wins on both reuse-adjusted cost and quality here, so it is the default pick. Reach for Kimi K2.6 only when a specific constraint (modality, latency floor, or licensing) forces it.

Grok 4.3 vs Kimi K2.6, answered.

Is Grok 4.3 or Kimi K2.6 cheaper?

At 55% prefix reuse, Grok 4.3 blends to about $1.13 per 1M tokens and Kimi K2.6 to about $1.39. Grok 4.3 is cheaper on that basis.

Which has the larger context window?

Grok 4.3 has the larger window: 1M vs 262K tokens.

Which captures more reuse?

Kimi K2.6 shows higher measured cache capture (81% vs 76%) in the Zumik corpus.

Let an alias pick for you.

Route to whichever model wins under current policy automatically. Zumik resolves the alias to the best fit per request, so you never hard-code a loser.