AI model comparison
GPT-6 Astra vs Gemini 3.1 Pro Preview
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
OpenAI
GPT-6 Astra
GPT-6 Astra is OpenAI's flagship model for demanding end-to-end work.
- Input / 1M
- $10
- Output / 1M
- $50
- Context
- 1.05M
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage across complex workflows.
- Input / 1M
- $2
- Output / 1M
- $12
- Context
- 1.05M
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Gemini 3.1 Pro Preview
4.5x cheaper for a typical chat
Higher intelligence score
GPT-6 Astra
52.7 vs 29.7 on Artificial Analysis
Larger context window
GPT-6 Astra
1.05M vs 1.05M tokens
Newer release
GPT-6 Astra
Released September 4, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
GPT-6 Astra52.7Gemini 3.1 Pro Preview29.7Coding index
GPT-6 Astra76.9Gemini 3.1 Pro Preview68.8Agentic index
GPT-6 Astra51Gemini 3.1 Pro Preview8.2Pricing
GPT-6 Astra vs Gemini 3.1 Pro Preview API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | GPT-6 Astra | Gemini 3.1 Pro Preview |
|---|---|---|
| Input tokensPer 1M tokens | $10 | $2 |
| Output tokensPer 1M tokens | $50 | $12 |
| Cached input (read)Per 1M tokens | $1 | $0.20 |
| Cache writePer 1M tokens | $12.50 | $0.38 |
| Long-context pricingPer 1M tokens, for very long prompts | $20 in / $75 out above 272K | $4 in / $18 out above 200K |
| Web searchPer request | $0.01 | $0.014 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
GPT-6 Astra$45Gemini 3.1 Pro Preview$10Coding task
30K in, 4K out
GPT-6 Astra$500$230 cachedGemini 3.1 Pro Preview$108$54 cachedLong document summary
150K in, 2K out
GPT-6 Astra$1600$250 cachedGemini 3.1 Pro Preview$324$54 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | GPT-6 Astra | Gemini 3.1 Pro Preview |
|---|---|---|
| Context window | 1.05M tokens | 1.05M tokens |
| Max output | 128K tokens | 66K tokens |
| Input types | File, Image, Text | Audio, File, Image, Text, Video |
| Output types | Text | Text |
| Reasoning effort levels | Max, Extra high, High, Medium, Low | High, Medium, Low |
| Default reasoning effort | Medium | Medium |
| Release date | September 4, 2026 | February 19, 2026 |
Features
Supported features
API features available for each model.
| Metric | GPT-6 Astra | Gemini 3.1 Pro Preview |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Not supported | Supported |
| Stop sequences | Not supported | Supported |
| Deterministic seed | Supported | Supported |
| Verbosity control | Supported | Not supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
GPT-6 AstraView full model details- GPT-6 Astra vs Claude Opus 5.5
- GPT-6 Astra vs Claude Sonnet 5.5
- GPT-6 Astra vs Claude Fable 5.1
- GPT-6 Astra vs GPT-6.1 Sol
- GPT-6 Astra vs Claude Opus 5
- GPT-6 Astra vs Claude Fable 5
- GPT-6 Astra vs Muse Spark 1.3
- GPT-6 Astra vs GPT-6 Sol
- GPT-6 Astra vs GPT-5.6 Sol
- GPT-6 Astra vs Grok 4.7
- GPT-6 Astra vs GLM 5.3
- GPT-6 Astra vs Kimi K3
- GPT-6 Astra vs GLM 5.3 Flash
- GPT-6 Astra vs Gemini 3.8 Flash
- GPT-6 Astra vs DeepSeek V4.1 Flash
- GPT-6 Astra vs MiMo-V2.6-Flash
- GPT-6 Astra vs Hy4 preview
- GPT-6 Astra vs GPT-6 Luna
- GPT-6 Astra vs DeepSeek V4 Flash 0731
Gemini 3.1 Pro PreviewView full model details- Gemini 3.1 Pro Preview vs Claude Opus 5.5
- Gemini 3.1 Pro Preview vs GLM 5.2
- Gemini 3.1 Pro Preview vs Gemini 3.5 Flash
- Gemini 3.1 Pro Preview vs GPT-5.3-Codex
- Gemini 3.1 Pro Preview vs Gemini 3 Flash Preview
- Gemini 3.1 Pro Preview vs Claude Opus 4.6
- Gemini 3.1 Pro Preview vs GPT-5.2
- Gemini 3.1 Pro Preview vs Claude Sonnet 4.6
- Gemini 3.1 Pro Preview vs Qwen3.7 Max
- Gemini 3.1 Pro Preview vs Claude Opus 4.5
- Gemini 3.1 Pro Preview vs GPT-5.2-Codex
Our take
GPT-6 Astra is the stronger general model here, with a much higher intelligence score (52.7 vs 29.7) and a 1.05M context window. Gemini 3.1 Pro is cheaper per output token and is the better fit if you want Google-native features rather than peak reasoning.
FAQ
Frequently asked questions
Is GPT-6 Astra or Gemini 3.1 Pro Preview cheaper?
Gemini 3.1 Pro Preview is cheaper for a typical chat (2K input tokens and 500 output tokens). Gemini 3.1 Pro Preview costs $2 per 1M input tokens and $12 per 1M output tokens, while GPT-6 Astra costs $10 per 1M input tokens and $50 per 1M output tokens.
Which has a bigger context window, GPT-6 Astra or Gemini 3.1 Pro Preview?
GPT-6 Astra supports up to 1.05M tokens of context, compared with 1.05M for Gemini 3.1 Pro Preview.
Is GPT-6 Astra smarter than Gemini 3.1 Pro Preview?
On the Artificial Analysis Intelligence Index, GPT-6 Astra scores 52.7 and Gemini 3.1 Pro Preview scores 29.7, putting GPT-6 Astra ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use GPT-6 Astra and Gemini 3.1 Pro Preview at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GPT-6 Astra and Gemini 3.1 Pro Preview answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to GPT-6 Astra and Gemini 3.1 Pro Preview at the same time. Compare the answers side by side and keep the best one.