Compare/Claude 4.5 Sonnet (Reasoning) vs Grok 3

Claude 4.5 Sonnet (Reasoning)vsGrok 3

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

Anthropic

Claude 4.5 Sonnet (Reasoning)

Input
$3.75/M
Output
$15/M
Speed
49 tok/s
TTFT
8.49s
xAI

Grok 3

Input
$3/M
Output
$15/M
Speed
37 tok/s
TTFT
0.65s

Winner by Category

Cheaper
Grok 3
Faster (tok/s)
Claude 4.5 Sonnet (Reasoning)
Lower Latency
Grok 3
Benchmarks (11-1)
Claude 4.5 Sonnet (Reasoning)

Pricing Comparison

MetricClaude 4.5 Sonnet (Reasoning)Grok 3
Input ($/M tokens)$3.75$3
Output ($/M tokens)$15$15
Cost for 1M input + 100K output tokens:
Claude 4.5 Sonnet (Reasoning)$5.25
Grok 3$4.50

Speed Comparison

Output Speed (tokens/s) — higher is better
Claude 4.5 Sonnet (Reasoning)
49 tok/s
Grok 3
37 tok/s
Time to First Token (seconds) — lower is better
Claude 4.5 Sonnet (Reasoning)
8.49s
Grok 3
0.65s

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
43.025.2
Coding Index
38.619.8
Math Index
88.058.0
GPQA Diamond
83.4%69.3%
MMLU-Pro
87.5%79.9%
LiveCodeBench
71.4%42.5%
AIME 2025
88.0%58.0%
MATH-500
87.0%
Humanity's Last Exam
17.3%5.1%
SciCode
44.7%36.8%
IFBench
57.3%46.9%
TerminalBench
35.6%11.4%
Claude 4.5 Sonnet (Reasoning)11 wins
1 winsGrok 3

Frequently Asked Questions

Which is cheaper, Claude 4.5 Sonnet (Reasoning) or Grok 3?

Grok 3 is cheaper overall. Its blended price (3:1 input/output ratio) is $6.00/M tokens vs $6.56/M for Claude 4.5 Sonnet (Reasoning).

Which model performs better on benchmarks?

Claude 4.5 Sonnet (Reasoning) wins 11 out of 12 benchmarks compared to 1 for Grok 3. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Claude 4.5 Sonnet (Reasoning) generates tokens faster at 49 tok/s vs 37 tok/s. However, Grok 3 has lower time-to-first-token (0.65s vs 8.49s).

When should I use Claude 4.5 Sonnet (Reasoning) vs Grok 3?

Choose based on your priorities: Grok 3 for lower cost, Claude 4.5 Sonnet (Reasoning) for stronger benchmark performance, and Claude 4.5 Sonnet (Reasoning) for faster generation. For latency-sensitive apps, check the TTFT comparison above.