Model comparison
Gemini 3.6 Flash vs GPT-5.6 Terra
Head-to-head evidence from 17 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemini 3.6 Flash unranked (Not scored); GPT-5.6 Terra #11 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemini 3.6 Flash and GPT-5.6 Terra share 17 comparable benchmark results. 1 of 8 categories are comparable. 2 results are unique to Gemini 3.6 Flash; 27 to GPT-5.6 Terra.
Updated July 21, 2026- Shared results
- 17
- Gemini 3.6 Flash only
- 2
- GPT-5.6 Terra only
- 27
- Comparable categories
- 1 / 8
Treat this as a split decision. Gemini 3.6 Flash makes more sense if you want the cheaper token bill; GPT-5.6 Terra is the better fit if agentic is the priority.
Confidence note. This is a partial-evidence comparison with 17 shared benchmark results across 5 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 3.6 Flash and GPT-5.6 Terra finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.
GPT-5.6 Terra is also the more expensive model on tokens at $2.50 input / $15.00 output per 1M tokens, versus $1.50 input / $7.50 output per 1M tokens for Gemini 3.6 Flash. That is roughly 2.0x on output cost alone.
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 3.6 Flash | Δ | GPT-5.6 Terra |
|---|---|---|---|
| Agentic | Gemini 3.6 Flash83.0 | Margin→ 4.4 | GPT-5.6 Terra87.4 |
| Coding | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Terra63.4 |
| Knowledge | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Terra92.9 |
| Math | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Terra80.8 |
| Multimodal | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Terra80.7 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemini 3.6 Flash | GPT-5.6 Terra | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemini 3.6 Flash$1.5 input / $7.5 output | GPT-5.6 Terra$2.5 input / $15 output | Gemini 3.6 Flash has the lower combined listed price. |
| Generation speedtokens per second | Gemini 3.6 FlashNot available | GPT-5.6 TerraNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Gemini 3.6 FlashNot available | GPT-5.6 TerraNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Gemini 3.6 Flash1M | GPT-5.6 Terra1M | Listed context windows are equal. |
Benchmark Deep Dive
AgenticGPT-5.6 Terra wins19 benchmarks
| Benchmark | Gemini 3.6 Flash | GPT-5.6 Terra | Result |
|---|---|---|---|
| OSWorld-VerifiedSource | 83% | — | Not comparable |
| GDPval-AASource | 1421 | 1581 | GPT-5.6 Terra leads |
| AA Agentic IndexSource | 38.7% | 47.4% | GPT-5.6 Terra leads |
| GDPval-AASource | 46.1% | 54.1% | GPT-5.6 Terra leads |
| AA BriefcaseSource | 961 | — | Not comparable |
| AA Tau3 BankingSource | 24.5% | 31.8% | GPT-5.6 Terra leads |
| aaTerminalBench21Source | 77.5% | 88% | GPT-5.6 Terra leads |
| Terminal-Bench 2.0Source | — | 87.4% | Not comparable |
| BrowseCompSource | — | 87.5% | Not comparable |
| OSWorld 2.0Source | — | 50.2% | Not comparable |
| CyberGymSource | — | 81.8% | Not comparable |
| ExploitGymSource | — | 23.2% | Not comparable |
| ToolathlonSource | — | 53.1% | Not comparable |
| τ²-bench resultsSource | — | 86.3% | Not comparable |
| AA Harvey LABSource | — | 85.2% | Not comparable |
| AA ITBenchSource | — | 51.0% | Not comparable |
| AA AutomationBenchSource | — | 45.6% | Not comparable |
| terminalBenchHardSource | — | 57.6% | Not comparable |
| APEX-Agents-AASource | — | 38.9% | Not comparable |
Coding7 benchmarks
| Benchmark | Gemini 3.6 Flash | GPT-5.6 Terra | Result |
|---|---|---|---|
| deepSweSource | 49% | 69.6% | GPT-5.6 Terra leads |
| AA Coding IndexSource | 69.2% | 76.7% | GPT-5.6 Terra leads |
| AA-SciCodeSource | 52.7% | 53.9% | GPT-5.6 Terra leads |
| SWE-bench ProSource | — | 63.4% | Not comparable |
| Terminal-Bench 2.0Source | — | 87.4% | Not comparable |
| FrontierCode 1.1 ExtendedSource | — | 55.8% | Not comparable |
| cursorBench32Source | — | 64.9% | Not comparable |
Reasoning3 benchmarks
Knowledge10 benchmarks
| Benchmark | Gemini 3.6 Flash | GPT-5.6 Terra | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 50.1% | 55.0% | GPT-5.6 Terra leads |
| AA-GPQA DiamondSource | 92.8% | 92.5% | Gemini 3.6 Flash leads |
| AA-HLESource | 38.3% | 41.8% | GPT-5.6 Terra leads |
| AA-Omniscience IndexSource | 23.5% | -0.2% | Gemini 3.6 Flash leads |
| AA-Omniscience AccuracySource | 50.2% | 45.9% | Gemini 3.6 Flash leads |
| AA-Omniscience Hallucination RateSource | 53.5% | 85.2% | Gemini 3.6 Flash leads |
| GPQASource | — | 92.9% | Not comparable |
| GPQA-DSource | — | 92.9% | Not comparable |
| HealthBench ProfessionalSource | — | 57.7% | Not comparable |
| HealthBench HardSource | — | 32.7% | Not comparable |
Math3 benchmarks
Multimodal3 benchmarks
Inst. Following1 benchmarks
| Benchmark | Gemini 3.6 Flash | GPT-5.6 Terra | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 71.2% | Not comparable |
Frequently Asked Questions (2)
Which is better, Gemini 3.6 Flash or GPT-5.6 Terra?
Gemini 3.6 Flash and GPT-5.6 Terra are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.
Which is better for agentic tasks, Gemini 3.6 Flash or GPT-5.6 Terra?
GPT-5.6 Terra has the edge for agentic tasks in this comparison, averaging 87.4 versus 83. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.
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