AI model comparison
GPT-6.1 Sol vs GPT-6 Astra
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
OpenAI
GPT-6.1 Sol
GPT-6.1 Sol is an upgrade to GPT-6 Sol from OpenAI, positioned below the flagship GPT-6 Astra in the GPT-6 series.
- Input / 1M
- $2
- Output / 1M
- $10
- Context
- 1.05M
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
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
GPT-6.1 Sol
5.0x cheaper for a typical chat
Higher intelligence score
GPT-6 Astra
52.7 vs 51.8 on Artificial Analysis
Larger context window
Tie
1.05M vs 1.05M tokens
Newer release
GPT-6.1 Sol
Released September 29, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
GPT-6.1 Sol51.8GPT-6 Astra52.7Coding index
GPT-6.1 SolNot availableGPT-6 Astra76.9Agentic index
GPT-6.1 SolNot availableGPT-6 Astra51Pricing
GPT-6.1 Sol vs GPT-6 Astra API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | GPT-6.1 Sol | GPT-6 Astra |
|---|---|---|
| Input tokensPer 1M tokens | $2 | $10 |
| Output tokensPer 1M tokens | $10 | $50 |
| Cached input (read)Per 1M tokens | $0.10 | $1 |
| Cache writePer 1M tokens | $2.50 | $12.50 |
| Long-context pricingPer 1M tokens, for very long prompts | $4 in / $15 out above 272K | $20 in / $75 out above 272K |
| Web searchPer request | $0.01 | $0.01 |
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-6.1 Sol$9GPT-6 Astra$45Coding task
30K in, 4K out
GPT-6.1 Sol$100$43 cachedGPT-6 Astra$500$230 cachedLong document summary
150K in, 2K out
GPT-6.1 Sol$320$35 cachedGPT-6 Astra$1600$250 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | GPT-6.1 Sol | GPT-6 Astra |
|---|---|---|
| Context window | 1.05M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Input types | File, Image, Text | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, Extra high, High, Medium, Low | Max, Extra high, High, Medium, Low |
| Default reasoning effort | Medium | Medium |
| Release date | September 29, 2026 | September 4, 2026 |
Features
Supported features
API features available for each model.
| Metric | GPT-6.1 Sol | GPT-6 Astra |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Not supported | Not supported |
| Stop sequences | Not supported | Not supported |
| Deterministic seed | Supported | Supported |
| Verbosity control | Supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
GPT-6.1 SolView full model details- GPT-6.1 Sol vs Claude Opus 5.5
- GPT-6.1 Sol vs Claude Sonnet 5.5
- GPT-6.1 Sol vs Claude Fable 5.1
- GPT-6.1 Sol vs Claude Opus 5
- GPT-6.1 Sol vs Claude Fable 5
- GPT-6.1 Sol vs Muse Spark 1.3
- GPT-6.1 Sol vs GPT-6 Sol
- GPT-6.1 Sol vs GPT-5.6 Sol
- GPT-6.1 Sol vs Grok 4.7
- GPT-6.1 Sol vs DeepSeek V4.1 Flash
- GPT-6.1 Sol vs GLM 5.3 Flash
- GPT-6.1 Sol vs MiMo-V2.6-Flash
- GPT-6.1 Sol vs GLM 5.3
- GPT-6.1 Sol vs Hy4 preview
- GPT-6.1 Sol vs GPT-6 Luna
- GPT-6.1 Sol vs Kimi K3
- GPT-6.1 Sol vs DeepSeek V4 Flash 0731
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 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
- GPT-6 Astra vs Gemini 3.1 Pro Preview
Our take
GPT-6.1 Sol is 5.0x cheaper for a typical chat. GPT-6 Astra scores higher on the Artificial Analysis Intelligence Index (52.7 vs 51.8). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is GPT-6.1 Sol or GPT-6 Astra cheaper?
GPT-6.1 Sol is cheaper for a typical chat (2K input tokens and 500 output tokens). GPT-6.1 Sol costs $2 per 1M input tokens and $10 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-6.1 Sol or GPT-6 Astra?
GPT-6.1 Sol supports up to 1.05M tokens of context, compared with 1.05M for GPT-6 Astra.
Is GPT-6.1 Sol smarter than GPT-6 Astra?
On the Artificial Analysis Intelligence Index, GPT-6.1 Sol scores 51.8 and GPT-6 Astra scores 52.7, 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-6.1 Sol and GPT-6 Astra at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GPT-6.1 Sol and GPT-6 Astra answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to GPT-6.1 Sol and GPT-6 Astra at the same time. Compare the answers side by side and keep the best one.