AI model comparison
GPT-6 Astra vs Muse Spark 1.3
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
Meta
Muse Spark 1.3
Muse Spark 1.3 is a multimodal reasoning model from Meta for long-running agentic, multi-agent, and coding workflows.
- Input / 1M
- $1.25
- Output / 1M
- $4.25
- Context
- 1.05M
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Muse Spark 1.3
9.7x cheaper for a typical chat
Higher intelligence score
GPT-6 Astra
52.7 vs 48.1 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 Astra52.7Coding index
GPT-6 Astra76.9Agentic index
GPT-6 Astra51Pricing
GPT-6 Astra vs Muse Spark 1.3 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | GPT-6 Astra | |
|---|---|---|
| Input tokensPer 1M tokens | $10 | $1.25 |
| Output tokensPer 1M tokens | $50 | $4.25 |
| Cached input (read)Per 1M tokens | $1 | $0.15 |
| Cache writePer 1M tokens | $12.50 | Not available |
| Long-context pricingPer 1M tokens, for very long prompts | $20 in / $75 out above 272K | Same rate at any length |
| Web searchPer request | $0.01 | $0.0025 |
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$45Coding task
30K in, 4K out
GPT-6 Astra$500$230 cachedLong document summary
150K in, 2K out
GPT-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 Astra | |
|---|---|---|
| Context window | 1.05M tokens | 1.05M tokens |
| Max output | 128K tokens | 944K tokens |
| Input types | File, Image, Text | File, Image, Text, Video |
| Output types | Text | Text |
| Reasoning effort levels | Max, Extra high, High, Medium, Low | Max, Extra high, High, Medium, Low, Minimal |
| Default reasoning effort | Medium | Medium |
| Release date | September 4, 2026 | September 2, 2026 |
Features
Supported features
API features available for each model.
| Metric | GPT-6 Astra | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Not supported | Supported |
| Stop sequences | Not supported | Not supported |
| Deterministic seed | Supported | Not 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 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
- Muse Spark 1.3 vs Claude Opus 5.5
- Muse Spark 1.3 vs Claude Sonnet 5.5
- Muse Spark 1.3 vs Claude Fable 5.1
- Muse Spark 1.3 vs GPT-6.1 Sol
- Muse Spark 1.3 vs Claude Opus 5
- Muse Spark 1.3 vs Claude Fable 5
- Muse Spark 1.3 vs GPT-6 Sol
- Muse Spark 1.3 vs GPT-5.6 Sol
- Muse Spark 1.3 vs Grok 4.7
- Muse Spark 1.3 vs MiMo-V2.6-Pro
- Muse Spark 1.3 vs Qwen3.8 Max (0902)
- Muse Spark 1.3 vs GLM 5.3
- Muse Spark 1.3 vs Grok 4.6
- Muse Spark 1.3 vs Gemini 3.8 Flash
- Muse Spark 1.3 vs DeepSeek V4.1 Flash
Our take
Muse Spark 1.3 is 9.7x cheaper for a typical chat. GPT-6 Astra scores higher on the Artificial Analysis Intelligence Index (52.7 vs 48.1). GPT-6 Astra has the larger context window (1.05M vs 1.05M tokens). 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 Astra or Muse Spark 1.3 cheaper?
Muse Spark 1.3 is cheaper for a typical chat (2K input tokens and 500 output tokens). Muse Spark 1.3 costs $1.25 per 1M input tokens and $4.25 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 Muse Spark 1.3?
GPT-6 Astra supports up to 1.05M tokens of context, compared with 1.05M for Muse Spark 1.3.
Is GPT-6 Astra smarter than Muse Spark 1.3?
On the Artificial Analysis Intelligence Index, GPT-6 Astra scores 52.7 and Muse Spark 1.3 scores 48.1, 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 Muse Spark 1.3 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GPT-6 Astra and Muse Spark 1.3 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to GPT-6 Astra and Muse Spark 1.3 at the same time. Compare the answers side by side and keep the best one.