GPT-5.6 Sol vs GPT-6 Astra
API pricing, context window and capabilities for GPT-5.6 Sol and GPT-6 Astra, side by side. Prices are the cheapest listed serving route per 1M tokens, from LiteLLM and OpenRouter.
Verdict
computed from the published numbersGPT-5.6 Sol wins on price and on Terminal-Bench. GPT-6 Astra wins on intelligence.
Price
GPT-5.6 Sol
Terminal-Bench
GPT-5.6 Sol
Intelligence
GPT-6 Astra
Context window
Tied
Key takeaways
who wins on what, from the published numbersGPT-5.6 Sol wins
- Cheaper input ($2.00 vs $10.00 /1M)
- Cheaper output ($10.00 vs $50.00 /1M)
- More serving providers (6 vs 5)
GPT-6 Astra wins
No clear edge on the tracked metrics.
Cheaper overall
GPT-5.6 Sol
$2.00 + $10.00 /1M
Larger context
Tied
More providers
GPT-5.6 Sol
6 providers
Pricing & specs
cheapest listed route · per 1M tokensOn-demand listed rates, OpenRouter routed quotes and Vercel reseller quotes. Enterprise commitments can be materially lower. An OpenRouter routed quote is the price of whichever upstream provider OpenRouter prefers today, so it moves day to day.
| GPT-5.6 Sol | GPT-6 Astra | |
|---|---|---|
| Input $/1M | $2.00OpenRouter routed quote best | $10.00via OpenAI |
| Output $/1M | $10.00OpenRouter routed quote best | $50.00via OpenAI |
| Context window | 1.1M | 1.1M |
| Max output | 128K | 128K |
| Serving providers | 6 best | 5 |
| Date | Released Jul 9, 2026 | Released Sep 4, 2026 |
Benchmarks
Benchmark scores, side by side| GPT-5.6 Sol | GPT-6 Astra | |
|---|---|---|
| Intelligence | 47.0 | 52.7 best |
| Terminal-Bench | 90% best | 88% |
| GPQA Diamond | 94% | 96% best |
| Output speed | 94 t/s best | 61 t/s |
| Latency (TTFT) | 138.40s best | 280.05s |
Cost calculator
choose a serving route for each sideInput tokens / month
Output tokens / month
GPT-5.6 Sol
via OpenRouter
$20
GPT-6 Astra
via OpenAI
$100
Capabilities
feature support, side by side| Feature | GPT-5.6 Sol | GPT-6 Astra |
|---|---|---|
| Vision | ✓ | ✓ |
| Tool use | ✓ | ✓ |
| Reasoning | ✓ | ✓ |
| Audio | — | — |
| Prompt caching | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Web search | ✓ | ✓ |
Related comparisons
Frequently asked questions
Which is cheaper, GPT-5.6 Sol or GPT-6 Astra?
GPT-5.6 Sol is cheaper for input ($2.00 vs $10.00 per 1M tokens) as an OpenRouter routed quote, while OpenAI lists it at $4.00 per 1M input. GPT-5.6 Sol is cheaper for output ($10.00 vs $50.00 per 1M tokens) as an OpenRouter routed quote, while OpenAI lists it at $20.00 per 1M output.
What is the context window difference between GPT-5.6 Sol and GPT-6 Astra?
Both GPT-5.6 Sol and GPT-6 Astra have about a 1.1M-token context window.
How do GPT-5.6 Sol and GPT-6 Astra compare on benchmarks?
On the tracked benchmarks, GPT-5.6 Sol leads on Terminal-Bench, and GPT-6 Astra leads on intelligence.
Listed prices from LiteLLM, OpenRouter and Vercel · last checked Oct 14, 2026
Every weekday
AI moves fast. Here's your debrief.
News, analysis, tools, and more.
For people who build with AI