Model comparison
GPT-5.5 Pro vs Grok Code Fast 1
Head-to-head evidence from 1 shared benchmark result across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-5.5 Pro #38 (Estimated); Grok Code Fast 1 #180 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.5 Pro and Grok Code Fast 1 share 1 comparable benchmark result. 0 of 8 categories are comparable. 6 results are unique to GPT-5.5 Pro; 11 to Grok Code Fast 1.
Updated July 22, 2026- Shared results
- 1
- GPT-5.5 Pro only
- 6
- Grok Code Fast 1 only
- 11
- Comparable categories
- 0 / 8
Benchmark data for GPT-5.5 Pro and Grok Code Fast 1 is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 1 shared benchmark result across 1 evidence category; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
GPT-5.5 Pro is priced at $30.00 input / $180.00 output per 1M tokens, versus $0.20 input / $1.50 output per 1M tokens for Grok Code Fast 1. GPT-5.5 Pro has the larger context window at 1M, compared with 256K for Grok Code Fast 1.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | GPT-5.5 Pro | Δ | Grok Code Fast 1 |
|---|---|---|---|
| Agentic | GPT-5.5 Pro90.1 | MarginNo overlap | Grok Code Fast 1Not measured |
| Coding | GPT-5.5 ProNot measured | MarginNo overlap | Grok Code Fast 170.8 |
| Knowledge | GPT-5.5 Pro57.2 | MarginNo overlap | Grok Code Fast 1Not measured |
| Math | GPT-5.5 Pro48.1 | MarginNo overlap | Grok Code Fast 1Not measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.5 Pro | Grok Code Fast 1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.5 Pro$30 input / $180 output | Grok Code Fast 1$0.2 input / $1.5 output | Grok Code Fast 1 has the lower combined listed price. |
| Generation speedtokens per second | GPT-5.5 ProNot available | Grok Code Fast 1172 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.5 ProNot available | Grok Code Fast 12.81 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.5 Pro1M | Grok Code Fast 1256K | GPT-5.5 Pro lists the larger context window. |
Benchmark Deep Dive
Agentic2 benchmarks
Coding2 benchmarks
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | GPT-5.5 Pro | Grok Code Fast 1 | Result |
|---|---|---|---|
| HLESource | 57.2% | — | Not comparable |
| HLE w/o toolsSource | 43.1% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 21.6% | Not comparable |
| AA-GPQA DiamondSource | — | 72.7% | Not comparable |
| AA-HLESource | — | 7.5% | Not comparable |
| AA-Omniscience IndexSource | — | -36.0% | Not comparable |
| AA-Omniscience AccuracySource | — | 23.8% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 78.5% | Not comparable |
Math3 benchmarks
Inst. Following1 benchmarks
| Benchmark | GPT-5.5 Pro | Grok Code Fast 1 | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 41.4% | Not comparable |
Frequently Asked Questions (3)
Can I compare GPT-5.5 Pro and Grok Code Fast 1 on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for GPT-5.5 Pro and Grok Code Fast 1 today?
GPT-5.5 Pro: $30.00 input / $180.00 output per 1M tokens Grok Code Fast 1: $0.20 input / $1.50 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
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