GPT-6 Astra vs Gemini 3.1 Pro
GPT-6 Astra wins on Overall, Coding; Gemini 3.1 Pro wins on Multimodal. Every numeric field is compared below, with a worked monthly-cost example and a pick rule for each use case.
Verdict at a glance
Choose GPT-6 Astra if you…
- Best-in-class computer use
- Frontier research & reasoning
- Autonomous long-horizon tasks
- Strongest cybersecurity (gated)
- Best for: Computer use, Deep research, Cybersecurity
Choose Gemini 3.1 Pro if you…
- Native audio and video
- Strong scientific computing
- Largest 2M context
- Search integration
- Best for: Multimodal, Scientific reasoning, Audio & video
Head-to-head aggregate scores
Scores are 0–100, aggregated from public benchmark information and independently weighted across three leaderboards. Rank is out of 26 tracked models.
Aggregated from public sources and independently weighted; methodology on the Terms page. Scores within 3 points are treated as statistically tied.
Specs & pricing — every field side by side
List API prices in USD per 1M tokens. The highlighted cell is the stronger value/capability on that row.
| Dimension | GPT-6 Astra | Gemini 3.1 Pro | Verdict |
|---|---|---|---|
| Vendor | OpenAI (US) | Google (US) | Different vendors |
| Released | 2026.09 | 2026.05 | GPT-6 Astra is newer |
| Overall (rank) | 96 · #1 | 83 · #5 | GPT-6 Astra +13 |
| Coding | 97 · #3 | 74 · #12 | GPT-6 Astra +23 |
| Multimodal | 90 · #7 | 92 · #3 | Gemini 3.1 Pro +2 |
| Context window | 1.05M | 2M | Gemini 3.1 Pro larger |
| Max output | 128K | 128K | Tie |
| Effective-context | 96 | 92 | GPT-6 Astra more reliable |
| Input $/1M | $10 | $2 | Gemini 3.1 Pro cheaper |
| Output $/1M | $50 | $12 | Gemini 3.1 Pro cheaper |
| Cache discount | 50% off | none | GPT-6 Astra deeper |
| Speed | ~35 tok/s | ~60 tok/s | Gemini 3.1 Pro faster |
| TTFT | 1.1s | 0.7s | Gemini 3.1 Pro snappier |
| Function calling | 94 | 78 | GPT-6 Astra ahead |
| Refusal rate | ~13% | ~12% | Gemini 3.1 Pro less restrictive |
| English | 99 | 90 | GPT-6 Astra |
| Chinese | 72 | 75 | Gemini 3.1 Pro |
| Modalities | text, image | text, image, audio, video | different coverage |
| Open weights | No | No | Both closed |
| Fine-tuning | No | Yes | |
| Free tier | No free API tier; Fast mode delivers up to ~2x throughput | Gemini App free with limited quota; API free tier available | |
| SOC2 / no-train | yes / yes | yes / yes | |
| Private deployment | No | No | Neither |
Fields drawn from vendor public documentation and the Modelspectra 26-model dataset; speed varies with network, concurrency and prompt length. Verify current pricing before purchase.
Dimension-by-dimension analysis
Reasoning & overall intelligence
GPT-6 Astra leads the overall aggregate by 13 points (96 vs 83). That is a meaningful, not marginal, edge on hard, multi-step reasoning, while Gemini 3.1 Pro remains a strong generalist that is not out of its depth on routine work.
Agentic coding
This is a decisive gap: GPT-6 Astra scores 97 against 74. On multi-file edits, SWE-style tickets and long-horizon agent loops GPT-6 Astra needs fewer correction turns; Gemini 3.1 Pro is still competent for scripts and assisted completion but trails as task complexity rises.
Multimodal
Gemini 3.1 Pro leads multimodal 92 vs 90. A concrete modality difference: Gemini 3.1 Pro additionally handles audio, video.
Speed & latency
Gemini 3.1 Pro is faster in interactive use: ~60 tok/s with 0.7s TTFT versus ~35 tok/s with 1.1s TTFT (about 1.7× the throughput). For conversational UIs where perceived responsiveness drives retention, that edge is a real product factor even when raw reasoning is lower.
Context: window vs usable recall
Nominal windows are 1.05M for GPT-6 Astra and 2M for Gemini 3.1 Pro. Crucially, the larger nominal window does not win on usable recall: Gemini 3.1 Pro advertises 2M but GPT-6 Astra scores higher on effective-context (96 vs 92), i.e. it actually retains more of what it was given.
Price & total cost
Gemini 3.1 Pro is the cheaper API at $2/$12 versus GPT-6 Astra at $10/$50 per 1M input/output tokens — list input is about 5.0× lower. Cache discounts (GPT-6 Astra 50%) shift the effective bill, worked out below.
Chinese vs English
English: GPT-6 Astra 99 vs Gemini 3.1 Pro 90. Chinese: 72 vs 75. Both are US-based models; for Chinese-first workloads also compare domestic models on the leaderboard.
Tool use & ecosystem
Function-calling score: GPT-6 Astra 94 vs Gemini 3.1 Pro 78, so GPT-6 Astra has the edge on structured tool use. Fine-tuning is available from Gemini 3.1 Pro. Factor in existing SDK/plugin familiarity — switching cost often outweighs a few-point tool-use gap.
Cost worked example — same workload, real token math
Assume a production workload of 100M input + 30M output tokens per month, with 90% of input tokens served from cache. Figures use public list prices.
| Scenario · per month | GPT-6 Astra | Gemini 3.1 Pro | Gap |
|---|---|---|---|
| List priceno cache applied | $2,500100M in × $10 + 30M out × $50 | $560100M in × $2 + 30M out × $12 | 4.46×gap |
| With caching90% of inputs cache-hit | $2,05090M cached in × $5 + 10M in × $10 + 30M out × $50 | $560no published cache discount | 3.66×gap |
Illustrative model; your input/output mix and cache-hit ratio change the result. Prices are list rates before any enterprise agreement.