Model comparison
GPT-5.5 vs o3-mini
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: GPT-5.5 #9 (Estimated); o3-mini #136 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.5 and o3-mini share 6 comparable benchmark results. 2 of 8 categories are comparable. 51 results are unique to GPT-5.5; 4 to o3-mini.
Updated July 22, 2026- Shared results
- 6
- GPT-5.5 only
- 51
- o3-mini only
- 4
- Comparable categories
- 2 / 8
Pick GPT-5.5 if you want the stronger benchmark profile. o3-mini 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 6 shared benchmark results across 3 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 is clearly ahead on the BenchAlign aggregate, 73.51 to 47.41. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.5's sharpest advantage is in coding, where it averages 58.6 against 49.3. The single biggest benchmark swing on the page is GPQA, 93.6% to 77.2%. o3-mini does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
GPT-5.5 is also the more expensive model on tokens at $5.00 input / $30.00 output per 1M tokens, versus $1.10 input / $4.40 output per 1M tokens for o3-mini. That is roughly 6.8x on output cost alone. GPT-5.5 gives you the larger context window at 1M, compared with 200K for o3-mini.
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 | Δ | o3-mini |
|---|---|---|---|
| Knowledge | GPT-5.557.8 | Margin→ 19.4 | o3-mini77.2 |
| Coding | GPT-5.558.6 | Margin← 9.3 | o3-mini49.3 |
| Agentic | GPT-5.581.6 | MarginNo overlap | o3-miniNot measured |
| Reasoning | GPT-5.585.0 | MarginNo overlap | o3-miniNot measured |
| Math | GPT-5.547.6 | MarginNo overlap | o3-miniNot measured |
| Multimodal | GPT-5.570.4 | MarginNo overlap | o3-miniNot measured |
| Inst. Following | GPT-5.5Not measured | MarginNo overlap | o3-mini93.9 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
GPQA
KnowledgeA 93.6%B 77.2%Winner: GPT-5.5Δ 16.4GPQA: GPT-5.5 scored 93.6%; o3-mini scored 77.2%. GPT-5.5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.5 | o3-mini | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.5$5 input / $30 output | o3-mini$1.1 input / $4.4 output | o3-mini has the lower combined listed price. |
| Generation speedtokens per second | GPT-5.5Not available | o3-mini160 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.5Not available | o3-mini7.12 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.51M | o3-mini200K | GPT-5.5 lists the larger context window. |
Benchmark Deep Dive
Agentic24 benchmarks
| Benchmark | GPT-5.5 | o3-mini | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 82% | — | Not comparable |
| CyberGymSource | 81.8% | — | Not comparable |
| BrowseCompSource | 84.4% | — | Not comparable |
| OSWorld-VerifiedSource | 78.7% | — | Not comparable |
| MCP AtlasSource | 75.3% | — | Not comparable |
| ToolathlonSource | 55.6% | — | Not comparable |
| τ²-bench resultsSource | 93.9% | 28.7% | GPT-5.5 leads |
| AA Agentic IndexSource | 44.9% | — | Not comparable |
| APEX-Agents-AASource | 37.7% | — | Not comparable |
| GDPval-AASource | 49.5% | — | Not comparable |
| GDPval-AASource | 1490 | — | Not comparable |
| Gert LabsSource | 72.93% | — | Not comparable |
| ResearchClawBenchSource | 17.0% | — | Not comparable |
| OSWorld 2.0Source | 13.0% | — | Not comparable |
| JobBenchSource | 42.7% | — | Not comparable |
| ExploitGymSource | 13.4% | — | Not comparable |
| AA BriefcaseSource | 1154 | — | Not comparable |
| AA AutomationBenchSource | 42.1% | — | Not comparable |
| AA EnterpriseOps-GymSource | 46.6% | — | Not comparable |
| AA Harvey LABSource | 86.3% | — | Not comparable |
| AA ITBenchSource | 45.8% | — | Not comparable |
| AA Tau3 BankingSource | 31.3% | — | Not comparable |
| terminalBenchHardSource | 60.6% | — | Not comparable |
| aaTerminalBench21Source | 84.3% | — | Not comparable |
CodingGPT-5.5 wins10 benchmarks
| Benchmark | GPT-5.5 | o3-mini | Result |
|---|---|---|---|
| SWE-bench ProSource | 58.6% | — | Not comparable |
| Terminal-Bench 2.0Source | 82.0% | — | Not comparable |
| Vibe Code BenchSource | 69.85% | — | Not comparable |
| React Native EvalsSource | 84.7% | — | Not comparable |
| cursorBench31Source | 59.2% | — | Not comparable |
| cursorBench32Source | 58.4% | — | Not comparable |
| AA Coding IndexSource | 74.9% | — | Not comparable |
| AA-SciCodeSource | 56.1% | 39.9% | GPT-5.5 leads |
| FrontierCode 1.1 MainSource | 43.0% | — | Not comparable |
| SWE-bench VerifiedSource | — | 49.3% | Not comparable |
Reasoning5 benchmarks
Knowledgeo3-mini wins11 benchmarks
| Benchmark | GPT-5.5 | o3-mini | Result |
|---|---|---|---|
| GPQASource | 93.6% | 77.2% | GPT-5.5 leads |
| GPQA-DSource | 93.6% | — | Not comparable |
| HLESource | 52.2% | — | Not comparable |
| HLE w/o toolsSource | 41.4% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 54.8% | 19.0% | GPT-5.5 leads |
| AA-GPQA DiamondSource | 93.5% | 74.8% | GPT-5.5 leads |
| AA-HLESource | 44.3% | 8.7% | GPT-5.5 leads |
| AA-Omniscience IndexSource | 20.1% | — | Not comparable |
| AA-Omniscience AccuracySource | 56.9% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 85.5% | — | Not comparable |
| MMLUSource | — | 86.9% | Not comparable |
Math4 benchmarks
Multimodal5 benchmarks
Frequently Asked Questions (3)
Which is better, GPT-5.5 or o3-mini?
GPT-5.5 is ahead on BenchLM's BenchAlign leaderboard, 73.51 to 47.41. The biggest single separator in this matchup is GPQA, where the scores are 93.6% and 77.2%.
Which is better for knowledge tasks, GPT-5.5 or o3-mini?
o3-mini has the edge for knowledge tasks in this comparison, averaging 77.2 versus 57.8. Inside this category, Artificial Analysis Intelligence Index is the benchmark that creates the most daylight between them.
Which is better for coding, GPT-5.5 or o3-mini?
GPT-5.5 has the edge for coding in this comparison, averaging 58.6 versus 49.3. Inside this category, AA-SciCode is the benchmark that creates the most daylight between them.
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