Compare/Claude Opus 4.5 (Reasoning) vs Grok 4

Claude Opus 4.5 (Reasoning)vsGrok 4

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

Anthropic

Claude Opus 4.5 (Reasoning)

Input
$6.25/M
Output
$25/M
Speed
54 tok/s
TTFT
11.25s
xAI

Grok 4

Input
$5.5/M
Output
$27.5/M
Speed
TTFT

Winner by Category

Cheaper
Claude Opus 4.5 (Reasoning)
Faster (tok/s)
Claude Opus 4.5 (Reasoning)
Lower Latency
Grok 4
Benchmarks (8-4)
Claude Opus 4.5 (Reasoning)

Pricing Comparison

MetricClaude Opus 4.5 (Reasoning)Grok 4
Input ($/M tokens)$6.25$5.5
Output ($/M tokens)$25$27.5
Cost for 1M input + 100K output tokens:
Claude Opus 4.5 (Reasoning)$8.75
Grok 4$8.25

Speed Comparison

Output Speed (tokens/s) — higher is better
Claude Opus 4.5 (Reasoning)
54 tok/s
Grok 4
Time to First Token (seconds) — lower is better
Claude Opus 4.5 (Reasoning)
11.25s
Grok 4

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
49.741.5
Coding Index
47.840.5
Math Index
91.392.7
GPQA Diamond
86.6%87.7%
MMLU-Pro
89.5%86.6%
LiveCodeBench
87.1%81.9%
AIME 2025
91.3%92.7%
MATH-500
99.0%
Humanity's Last Exam
28.4%23.9%
SciCode
49.5%45.7%
IFBench
58.0%53.7%
TerminalBench
47.0%37.9%
Claude Opus 4.5 (Reasoning)8 wins
4 winsGrok 4

Frequently Asked Questions

Which is cheaper, Claude Opus 4.5 (Reasoning) or Grok 4?

Claude Opus 4.5 (Reasoning) is cheaper overall. Its blended price (3:1 input/output ratio) is $10.94/M tokens vs $11.00/M for Grok 4.

Which model performs better on benchmarks?

Claude Opus 4.5 (Reasoning) wins 8 out of 12 benchmarks compared to 4 for Grok 4. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Claude Opus 4.5 (Reasoning) generates tokens faster at 54 tok/s vs 0 tok/s. However, Grok 4 has lower time-to-first-token (0.00s vs 11.25s).

When should I use Claude Opus 4.5 (Reasoning) vs Grok 4?

Choose based on your priorities: Claude Opus 4.5 (Reasoning) for lower cost, Claude Opus 4.5 (Reasoning) for stronger benchmark performance, and Claude Opus 4.5 (Reasoning) for faster generation. For latency-sensitive apps, check the TTFT comparison above.