AI model comparison
Claude Opus 5.5 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.
Anthropic
Claude Opus 5.5
Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5.
- Input / 1M
- $4
- Output / 1M
- $20
- Context
- 1M
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
3.9x cheaper for a typical chat
Higher intelligence score
Claude Opus 5.5
57.6 vs 48.1 on Artificial Analysis
Larger context window
Muse Spark 1.3
1.05M vs 1M tokens
Newer release
Claude Opus 5.5
Released September 22, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Claude Opus 5.557.6Coding index
Claude Opus 5.5Not availableAgentic index
Claude Opus 5.5Not availablePricing
Claude Opus 5.5 vs Muse Spark 1.3 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Claude Opus 5.5 | |
|---|---|---|
| Input tokensPer 1M tokens | $4 | $1.25 |
| Output tokensPer 1M tokens | $20 | $4.25 |
| Cached input (read)Per 1M tokens | $0.20 | $0.15 |
| Cache writePer 1M tokens | $5 | Not available |
| 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
Claude Opus 5.5$18Coding task
30K in, 4K out
Claude Opus 5.5$200$86 cachedLong document summary
150K in, 2K out
Claude Opus 5.5$640$70 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Claude Opus 5.5 | |
|---|---|---|
| Context window | 1M 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 | High | Medium |
| Release date | September 22, 2026 | September 2, 2026 |
Features
Supported features
API features available for each model.
| Metric | Claude Opus 5.5 | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Not supported | Supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Not 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.
Claude Opus 5.5View full model details- Claude Opus 5.5 vs Claude Sonnet 5.5
- Claude Opus 5.5 vs Claude Fable 5.1
- Claude Opus 5.5 vs GPT-6 Astra
- Claude Opus 5.5 vs GPT-6.1 Sol
- Claude Opus 5.5 vs Claude Opus 5
- Claude Opus 5.5 vs Claude Fable 5
- Claude Opus 5.5 vs DeepSeek V4.1 Flash
- Claude Opus 5.5 vs GLM 5.3 Flash
- Claude Opus 5.5 vs GPT-6 Sol
- Claude Opus 5.5 vs MiMo-V2.6-Flash
- Claude Opus 5.5 vs GPT-5.6 Sol
- Claude Opus 5.5 vs Hy4 preview
- Claude Opus 5.5 vs Grok 4.7
- Claude Opus 5.5 vs GPT-6 Luna
- Claude Opus 5.5 vs DeepSeek V4 Flash 0731
- Claude Opus 5.5 vs GLM 5.3
- Claude Opus 5.5 vs Kimi K3
- Claude Opus 5.5 vs DeepSeek V4 Flash 0423
- Claude Opus 5.5 vs Step 5 Preview
- Claude Opus 5.5 vs Gemini 3.8 Flash
- Claude Opus 5.5 vs Hy3
- Claude Opus 5.5 vs Gemini 3.1 Pro Preview
- 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 Astra
- 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 3.9x cheaper for a typical chat. Claude Opus 5.5 scores higher on the Artificial Analysis Intelligence Index (57.6 vs 48.1). Muse Spark 1.3 has the larger context window (1.05M vs 1M 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 Claude Opus 5.5 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 Claude Opus 5.5 costs $4 per 1M input tokens and $20 per 1M output tokens.
Which has a bigger context window, Claude Opus 5.5 or Muse Spark 1.3?
Muse Spark 1.3 supports up to 1.05M tokens of context, compared with 1M for Claude Opus 5.5.
Is Claude Opus 5.5 smarter than Muse Spark 1.3?
On the Artificial Analysis Intelligence Index, Claude Opus 5.5 scores 57.6 and Muse Spark 1.3 scores 48.1, putting Claude Opus 5.5 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Claude Opus 5.5 and Muse Spark 1.3 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Claude Opus 5.5 and Muse Spark 1.3 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Claude Opus 5.5 and Muse Spark 1.3 at the same time. Compare the answers side by side and keep the best one.