Model comparison
Gemini 3 Flash vs GPT-5.1
Head-to-head evidence from 17 shared benchmark results across 7 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemini 3 Flash #49 (Supported); GPT-5.1 #94 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemini 3 Flash and GPT-5.1 share 17 comparable benchmark results. 1 of 8 categories are comparable. 2 results are unique to Gemini 3 Flash; 4 to GPT-5.1.
Updated July 20, 2026- Shared results
- 17
- Gemini 3 Flash only
- 2
- GPT-5.1 only
- 4
- Comparable categories
- 1 / 8
Pick Gemini 3 Flash if you want the stronger benchmark profile. GPT-5.1 only becomes the better choice if you want the stronger reasoning-first profile.
Confidence note. This is a partial-evidence comparison with 17 shared benchmark results across 7 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Gemini 3 Flash is clearly ahead on the BenchAlign aggregate, 60.49 to 53.65. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Gemini 3 Flash's sharpest advantage is in mathematics, where it averages 27.8 against 26.4. The single biggest benchmark swing on the page is FrontierMath v2 (Tier 4), 4.167% to 12.500%.
GPT-5.1 is also the more expensive model on tokens at $1.25 input / $10.00 output per 1M tokens, versus $0.50 input / $3.00 output per 1M tokens for Gemini 3 Flash. That is roughly 3.3x on output cost alone. GPT-5.1 is the reasoning model in the pair, while Gemini 3 Flash is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Gemini 3 Flash gives you the larger context window at 1M, 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 3 Flash | Δ | GPT-5.1 |
|---|---|---|---|
| Math | Gemini 3 Flash27.8 | Margin← 1.4 | GPT-5.126.4 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
FrontierMath v2 (Tier 4)
MathA 4.167%B 12.500%Winner: GPT-5.1Δ 8.3FrontierMath v2 (Tier 4): Gemini 3 Flash scored 4.167%; GPT-5.1 scored 12.500%. GPT-5.1 wins this benchmark. - Source ↗
FrontierMath v2 (Tiers 1-3)
MathA 35.640%B 31.034%Winner: Gemini 3 FlashΔ 4.6FrontierMath v2 (Tiers 1-3): Gemini 3 Flash scored 35.640%; GPT-5.1 scored 31.034%. Gemini 3 Flash wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemini 3 Flash | GPT-5.1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemini 3 Flash$0.5 input / $3 output | GPT-5.1$1.25 input / $10 output | Gemini 3 Flash has the lower combined listed price. |
| Generation speedtokens per second | Gemini 3 Flash159 tok/s | GPT-5.1111 tok/s | Gemini 3 Flash has the higher measured throughput. |
| First-answer latencyseconds to first token | Gemini 3 Flash1.19 s | GPT-5.157.47 s | Gemini 3 Flash reaches the first token sooner. |
| Context windowmaximum listed tokens | Gemini 3 Flash1M | GPT-5.1200K | Gemini 3 Flash lists the larger context window. |
Benchmark Deep Dive
Agentic7 benchmarks
| Benchmark | Gemini 3 Flash | GPT-5.1 | Result |
|---|---|---|---|
| Claw-EvalSource | 49.2% | — | Not comparable |
| τ²-bench resultsSource | 43.3% | 81.9% | GPT-5.1 leads |
| Gert LabsSource | 56.63% | 41.24% | Gemini 3 Flash leads |
| JobBenchSource | 11.4% | — | Not comparable |
| AA Agentic IndexSource | — | 21.0% | Not comparable |
| GDPval-AASource | — | 24.4% | Not comparable |
| GDPval-AASource | — | 987 | Not comparable |
Coding3 benchmarks
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | Gemini 3 Flash | GPT-5.1 | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 27.4% | 36.9% | GPT-5.1 leads |
| AA-GPQA DiamondSource | 81.2% | 87.3% | GPT-5.1 leads |
| AA-HLESource | 14.1% | 26.5% | GPT-5.1 leads |
| AA-Omniscience IndexSource | -3.6% | 5.6% | GPT-5.1 leads |
| AA-Omniscience AccuracySource | 45.5% | 37.6% | Gemini 3 Flash leads |
| AA-Omniscience Hallucination RateSource | 90.2% | 51.3% | GPT-5.1 leads |
MathGemini 3 Flash wins2 benchmarks
Multimodal2 benchmarks
Inst. Following1 benchmarks
| Benchmark | Gemini 3 Flash | GPT-5.1 | Result |
|---|---|---|---|
| AA-IFBenchSource | 55.1% | 72.9% | GPT-5.1 leads |
Frequently Asked Questions (2)
Which is better, Gemini 3 Flash or GPT-5.1?
Gemini 3 Flash is ahead on BenchLM's BenchAlign leaderboard, 60.49 to 53.65. The biggest single separator in this matchup is FrontierMath v2 (Tier 4), where the scores are 4.167% and 12.500%.
Which is better for math, Gemini 3 Flash or GPT-5.1?
Gemini 3 Flash has the edge for math in this comparison, averaging 27.8 versus 26.4. Inside this category, FrontierMath v2 (Tier 4) is the benchmark that creates the most daylight between them.
Related Comparisons
Explore More
Choose a model with this week’s evidence
Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.
One email each week. Unsubscribe anytime.