Model comparison
GPT-4.1 vs GPT-5.5 Pro
Head-to-head evidence from 3 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-4.1 #108 (Supported); GPT-5.5 Pro #38 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-4.1 and GPT-5.5 Pro share 3 comparable benchmark results. 2 of 8 categories are comparable. 17 results are unique to GPT-4.1; 4 to GPT-5.5 Pro.
Updated July 22, 2026- Shared results
- 3
- GPT-4.1 only
- 17
- GPT-5.5 Pro only
- 4
- Comparable categories
- 2 / 8
Pick GPT-5.5 Pro if you want the stronger benchmark profile. GPT-4.1 only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 3 shared benchmark results across 2 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
GPT-5.5 Pro is clearly ahead on the BenchAlign aggregate, 63.69 to 51.11. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.5 Pro's sharpest advantage is in mathematics, where it averages 48.1 against 4.1. The single biggest benchmark swing on the page is FrontierMath v2 (Tiers 1-3), 5.517% to 51.000%. GPT-4.1 does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
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 / $8.00 output per 1M tokens for GPT-4.1. That is roughly 22.5x on output cost alone. GPT-5.5 Pro is the reasoning model in the pair, while GPT-4.1 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.
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-4.1 | Δ | GPT-5.5 Pro |
|---|---|---|---|
| Math | GPT-4.14.1 | Margin→ 44.0 | GPT-5.5 Pro48.1 |
| Knowledge | GPT-4.166.3 | Margin← 9.1 | GPT-5.5 Pro57.2 |
| Agentic | GPT-4.1Not measured | MarginNo overlap | GPT-5.5 Pro90.1 |
| Coding | GPT-4.154.6 | MarginNo overlap | GPT-5.5 ProNot measured |
| Inst. Following | GPT-4.187.4 | MarginNo overlap | GPT-5.5 ProNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
FrontierMath v2 (Tiers 1-3)
MathA 5.517%B 51.000%Winner: GPT-5.5 ProΔ 45.5FrontierMath v2 (Tiers 1-3): GPT-4.1 scored 5.517%; GPT-5.5 Pro scored 51.000%. GPT-5.5 Pro wins this benchmark. - Source ↗
FrontierMath v2 (Tier 4)
MathA 0.000%B 39.600%Winner: GPT-5.5 ProΔ 39.6FrontierMath v2 (Tier 4): GPT-4.1 scored 0.000%; GPT-5.5 Pro scored 39.600%. GPT-5.5 Pro wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-4.1 | GPT-5.5 Pro | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-4.1$2 input / $8 output | GPT-5.5 Pro$30 input / $180 output | GPT-4.1 has the lower combined listed price. |
| Generation speedtokens per second | GPT-4.1108 tok/s | GPT-5.5 ProNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-4.11.02 s | GPT-5.5 ProNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-4.11M | GPT-5.5 Pro1M | Listed context windows are equal. |
Benchmark Deep Dive
Agentic3 benchmarks
Coding2 benchmarks
Reasoning2 benchmarks
KnowledgeGPT-4.1 wins10 benchmarks
| Benchmark | GPT-4.1 | GPT-5.5 Pro | Result |
|---|---|---|---|
| MMLUSource | 90.2% | — | Not comparable |
| GPQASource | 66.3% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 19.4% | — | Not comparable |
| AA-GPQA DiamondSource | 66.6% | — | Not comparable |
| AA-HLESource | 4.6% | — | Not comparable |
| AA-Omniscience IndexSource | -36.2% | — | Not comparable |
| AA-Omniscience AccuracySource | 24.2% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 79.6% | — | Not comparable |
| HLESource | — | 57.2% | Not comparable |
| HLE w/o toolsSource | — | 43.1% | Not comparable |
MathGPT-5.5 Pro wins3 benchmarks
Multimodal2 benchmarks
Frequently Asked Questions (3)
Which is better, GPT-4.1 or GPT-5.5 Pro?
GPT-5.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 63.69 to 51.11. The biggest single separator in this matchup is FrontierMath v2 (Tiers 1-3), where the scores are 5.517% and 51.000%.
Which is better for knowledge tasks, GPT-4.1 or GPT-5.5 Pro?
GPT-4.1 has the edge for knowledge tasks in this comparison, averaging 66.3 versus 57.2. GPT-5.5 Pro stays close enough that the answer can still flip depending on your workload.
Which is better for math, GPT-4.1 or GPT-5.5 Pro?
GPT-5.5 Pro has the edge for math in this comparison, averaging 48.1 versus 4.1. Inside this category, FrontierMath v2 (Tiers 1-3) 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.