Compare/Kimi K2 Thinking vs Grok 4.3 (medium)

Kimi K2 ThinkingvsGrok 4.3 (medium)

Side-by-side comparison of pricing, 12 benchmarks, and generation speed.

Kimi

Kimi K2 Thinking

Input
$0.6/M
Output
$2.5/M
Speed
168 tok/s
TTFT
0.78s
SpaceXAI

Grok 4.3 (medium)

Input
$1.25/M
Output
$2.5/M
Speed
103 tok/s
TTFT
21.73s

Winner by Category

Cheaper
Kimi K2 Thinking
Faster (tok/s)
Kimi K2 Thinking
Lower Latency
Kimi K2 Thinking
Benchmarks (5-5)
Tie

Pricing Comparison

MetricKimi K2 ThinkingGrok 4.3 (medium)
Input ($/M tokens)$0.6$1.25
Output ($/M tokens)$2.5$2.5
Cost for 1M input + 100K output tokens:
Kimi K2 Thinking$0.85
Grok 4.3 (medium)$1.50

Speed Comparison

Output Speed (tokens/s) — higher is better
Kimi K2 Thinking
168 tok/s
Grok 4.3 (medium)
103 tok/s
Time to First Token (seconds) — lower is better
Kimi K2 Thinking
0.78s
Grok 4.3 (medium)
21.73s

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
32.736.0
Coding Index
Math Index
94.7
GPQA Diamond
83.8%89.0%
MMLU-Pro
84.8%
LiveCodeBench
85.3%
AIME 2025
94.7%
MATH-500
Humanity's Last Exam
22.3%28.1%
SciCode
42.4%44.6%
IFBench
68.1%83.3%
TerminalBench
31.1%30.3%
Kimi K2 Thinking5 wins
5 winsGrok 4.3 (medium)

Frequently Asked Questions

Which is cheaper, Kimi K2 Thinking or Grok 4.3 (medium)?

Kimi K2 Thinking is cheaper overall. Its blended price (3:1 input/output ratio) is $1.07/M tokens vs $1.56/M for Grok 4.3 (medium).

Which model performs better on benchmarks?

It's a tie — both models win 5 benchmarks each across 12 evaluated categories. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Kimi K2 Thinking generates tokens faster at 168 tok/s vs 103 tok/s. Kimi K2 Thinking also has lower time-to-first-token (0.78s vs 21.73s).

When should I use Kimi K2 Thinking vs Grok 4.3 (medium)?

Choose based on your priorities: Kimi K2 Thinking for lower cost, both perform similarly on benchmarks, and Kimi K2 Thinking for faster generation. For latency-sensitive apps, check the TTFT comparison above.