GPT-5.5 Pro vs Grok 4.5
Head-to-head comparison across 1benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
Verdict
GPT-5.5 Pro leads for most workloads.
- Grok 4.5 is ~15× cheaper on input tokens — the budget pick.
Based on BenchLM composite scores, July 2026.
GPT-5.5 Pro
77
Grok 4.5
75
Pick GPT-5.5 Pro if you want the stronger benchmark profile. Grok 4.5 only becomes the better choice if you want the cheaper token bill.
Category Breakdown
| Benchmark | GPT-5.5 Pro | Δ | Grok 4.5 |
|---|---|---|---|
| Agentic | 90.1 | ← 6.8 | 83.3 |
| Coding | — | — | 64.7 |
| Knowledge | 57.2 | — | — |
| Math | 52.4 | — | — |
Operational Comparison
GPT-5.5 Pro
Grok 4.5
$30 / $180
$2 / $6
N/A
N/A
N/A
N/A
1M
500K
Quick Verdict
Pick GPT-5.5 Pro if you want the stronger benchmark profile. Grok 4.5 only becomes the better choice if you want the cheaper token bill.
GPT-5.5 Pro has the cleaner provisional overall profile here, landing at 77 versus 75. It is a real lead, but still close enough that category-level strengths matter more than the headline number.
GPT-5.5 Pro's sharpest advantage is in agentic, where it averages 90.1 against 83.3.
GPT-5.5 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $2.00 input / $6.00 output per 1M tokens for Grok 4.5. That is roughly 30.0x on output cost alone. GPT-5.5 Pro gives you the larger context window at 1M, compared with 500K for Grok 4.5.
Benchmark Deep Dive
Frequently Asked Questions (2)
Which is better, GPT-5.5 Pro or Grok 4.5?
GPT-5.5 Pro is ahead on BenchLM's provisional leaderboard, 77 to 75.
Which is better for agentic tasks, GPT-5.5 Pro or Grok 4.5?
GPT-5.5 Pro has the edge for agentic tasks in this comparison, averaging 90.1 versus 83.3. Grok 4.5 stays close enough that the answer can still flip depending on your workload.
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