Model comparison
Gemini 1.5 Pro vs GPT-5.1
Head-to-head evidence from 6 shared benchmark results across 3 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemini 1.5 Pro #185 (Supported); GPT-5.1 #94 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemini 1.5 Pro and GPT-5.1 share 6 comparable benchmark results. 0 of 8 categories are comparable. 0 results are unique to Gemini 1.5 Pro; 15 to GPT-5.1.
Updated July 20, 2026- Shared results
- 6
- Gemini 1.5 Pro only
- 0
- GPT-5.1 only
- 15
- Comparable categories
- 0 / 8
Benchmark data for Gemini 1.5 Pro and GPT-5.1 is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 6 shared benchmark results across 3 evidence categories; 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-5.1 is priced at $1.25 input / $10.00 output per 1M tokens, versus $1.25 input / $5.00 output per 1M tokens for Gemini 1.5 Pro. Gemini 1.5 Pro has the larger context window at 2M, compared with 200K for GPT-5.1.
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 | Gemini 1.5 Pro | Δ | GPT-5.1 |
|---|---|---|---|
| Math | Gemini 1.5 ProNot measured | MarginNo overlap | GPT-5.126.4 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemini 1.5 Pro | GPT-5.1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemini 1.5 Pro$1.25 input / $5 output | GPT-5.1$1.25 input / $10 output | Gemini 1.5 Pro has the lower combined listed price. |
| Generation speedtokens per second | Gemini 1.5 ProNot available | GPT-5.1111 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Gemini 1.5 ProNot available | GPT-5.157.47 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Gemini 1.5 Pro2M | GPT-5.1200K | Gemini 1.5 Pro lists the larger context window. |
Benchmark Deep Dive
Agentic5 benchmarks
Coding3 benchmarks
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | Gemini 1.5 Pro | GPT-5.1 | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 10.0% | 36.9% | GPT-5.1 leads |
| AA-GPQA DiamondSource | 58.9% | 87.3% | GPT-5.1 leads |
| AA-HLESource | 4.9% | 26.5% | GPT-5.1 leads |
| AA-Omniscience IndexSource | — | 5.6% | Not comparable |
| AA-Omniscience AccuracySource | — | 37.6% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 51.3% | Not comparable |
Math2 benchmarks
Multimodal2 benchmarks
Inst. Following1 benchmarks
| Benchmark | Gemini 1.5 Pro | GPT-5.1 | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 72.9% | Not comparable |
Frequently Asked Questions (3)
Can I compare Gemini 1.5 Pro and GPT-5.1 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 Gemini 1.5 Pro and GPT-5.1 today?
Gemini 1.5 Pro: $1.25 input / $5.00 output per 1M tokens GPT-5.1: $1.25 input / $10.00 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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