Gemini 4 Argon vs Muse Spark Open vs Claude Sonnet 5.5
Too close to call on our weighted score (Gemini 4 Argon 74, Claude Sonnet 5.5 72, Muse Spark Open 68). The right pick depends on what you value most.
Google
Gemini 4 Argon
74/100- ECI166.1
- Price$2.00 / $10.00
- Context1.05M
Meta
Muse Spark Open
68/100- ECI155.1
- Price$1.25 / $4.25
- Context1.05M
Anthropic
Claude Sonnet 5.5
72/100- ECI166.7
- Price$2.00 / $10.00
- Context1M
Too close to call
It is close. Our weighted score puts them within 3 points (Gemini 4 Argon 74/100, Claude Sonnet 5.5 72/100, Muse Spark Open 68/100), so choose by what matters most for your work: Claude Sonnet 5.5 for raw capability and Muse Spark Open on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityClaude Sonnet 5.5Capabilities Index (ECI): Claude Sonnet 5.5 166.7 · Gemini 4 Argon 166.1 · Muse Spark Open 155.1
- Lowest priceMuse Spark OpenMuse Spark Open $2.00 · Gemini 4 Argon $4.00 · Claude Sonnet 5.5 $4.00 per 1M tokens (3:1 blend)
- Longest contextGemini 4 Argon and Muse Spark OpenGemini 4 Argon 1,048,576 · Muse Spark Open 1,048,576 · Claude Sonnet 5.5 1,000,000 tokens
- Widest inputsGemini 4 ArgonGemini 4 Argon: Text, Images, PDFs, Audio, Video · Muse Spark Open: Text, Images, Audio, Video · Claude Sonnet 5.5: Text, Images, PDFs
- Self-hostingMuse Spark OpenPublishes downloadable weights (Muse Model License)
| Measure | Weight | Gemini 4 Argon | Muse Spark Open | Claude Sonnet 5.5 |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 96 | 83 | 97 |
| Price | 25% | 20 | 34 | 20 |
| Inputs & features | 15% | 100 | 80 | 80 |
| Context window | 10% | 61 | 61 | 60 |
| Overall | 100% | 74/100 | 68/100 | 72/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | |||
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 166.1 | 155.1 | 166.7 (best) |
| ECI rank | #7 of 165 | #39 of 165 | #5 of 165 (best) |
| GPQA DiamondGraduate-level science questions | 96.4% (best) | 88.6% | 95.6% |
| FrontierMath Tiers 1–3Research-level mathematics | 86.0% | 69.8% | 88.8% (best) |
| OTIS Mock AIME 2024–2025Competition mathematics | 100% (best) | 98.1% | 100% (best) |
| SimpleQA VerifiedShort factual questions | 76.0% (best) | 56.6% | 46.5% |
| Price per million tokens | |||
| Input | $2.00 | $1.25 (best) | $2.00 |
| Output | $10.00 | $4.25 (best) | $10.00 |
| Cached input | $0.10 | — | $0.10 |
| Blended (3:1) | $4.00 | $2.00 (best) | $4.00 |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official Google API | Median of 16 providers | Official Anthropic API |
| Limits | |||
| Context window | 1,048,576 tokens (best) | 1,048,576 tokens (best) | 1,000,000 tokens |
| Max output | 65,536 tokens | 131,072 tokens (best) | 128,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | Yes | No | Yes |
| Audio | Yes | Yes | No |
| Video | Yes | Yes | No |
| Reasoning | Yeslow · medium · high | Yes | Yeslow · medium · high · xhigh · max |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | No | Yes |
| Availability | |||
| Weights | Proprietary | OpenMuse Model License | Proprietary |
| API model ID | gemini-4-argon | — | claude-sonnet-5-5 |
| API providers | 24 | 16 | 34 (best) |
| Released | Oct 13, 2026 | Oct 15, 2026 | Sep 28, 2026 |
| Knowledge cutoff | Mar 2026 | Jan 4, 2026 | Jun 2026 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
Gemini 4 Argon$40.00
Muse Spark Open$21.00
Claude Sonnet 5.5$40.00
Which should you choose?
Which is better: Gemini 4 Argon, Muse Spark Open or Claude Sonnet 5.5?
It is close. Our weighted score puts them within 3 points (Gemini 4 Argon 74/100, Claude Sonnet 5.5 72/100, Muse Spark Open 68/100), so choose by what matters most for your work: Claude Sonnet 5.5 for raw capability and Muse Spark Open on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, Gemini 4 Argon, Muse Spark Open or Claude Sonnet 5.5?
Muse Spark Open is cheaper at $1.25 input / $4.25 output per million tokens (median across 16 API providers). Gemini 4 Argon costs $2.00 input / $10.00 output per million tokens (official Google API price); Claude Sonnet 5.5 costs $2.00 input / $10.00 output per million tokens (official Anthropic API price). At a typical mix of three input tokens to one output token, that is $2.00 per million tokens for Muse Spark Open versus $4.00 for Gemini 4 Argon (2× as much) and $4.00 for Claude Sonnet 5.5 (2× as much).
Which scores higher on benchmarks?
Claude Sonnet 5.5 scores higher on the Capabilities Index (ECI): Claude Sonnet 5.5 166.7 (#5 of 165), Gemini 4 Argon 166.1 (#7 of 165) and Muse Spark Open 155.1 (#39 of 165). The confidence ranges of the top two overlap (163.6–171.3 vs 163.1–170.3), so treat the gap as small. On individual benchmarks: GPQA Diamond — Gemini 4 Argon 96.4%, Claude Sonnet 5.5 95.6%, Muse Spark Open 88.6%; FrontierMath Tiers 1–3 — Claude Sonnet 5.5 88.8%, Gemini 4 Argon 86.0%, Muse Spark Open 69.8%; OTIS Mock AIME 2024–2025 — Gemini 4 Argon 100%, Claude Sonnet 5.5 100%, Muse Spark Open 98.1%; SimpleQA Verified — Gemini 4 Argon 76.0%, Muse Spark Open 56.6%, Claude Sonnet 5.5 46.5%.
Which is better for coding?
There are no published SWE-bench Verified results for Gemini 4 Argon, Muse Spark Open and Claude Sonnet 5.5 yet, so there is no like-for-like coding score. On overall capability, Claude Sonnet 5.5 leads, which tends to carry over to coding, but test on your own codebase. All three support tool calling for agent workflows.
Which has the bigger context window?
Gemini 4 Argon and Muse Spark Open have the largest context windows (1,048,576 and 1,048,576 tokens), against 1,000,000 for Claude Sonnet 5.5. Maximum output per response: Gemini 4 Argon up to 65,536, Muse Spark Open up to 131,072, Claude Sonnet 5.5 up to 128,000 tokens.
Which can read images, PDFs, audio or video?
Gemini 4 Argon accepts text, images, PDFs, audio and video; Muse Spark Open accepts text, images, audio and video; Claude Sonnet 5.5 accepts text, images and PDFs. Gemini 4 Argon handles the widest range of inputs.
Are any of these open source?
Muse Spark Open publishes its weights (Muse Model License) and can be self-hosted; Gemini 4 Argon and Claude Sonnet 5.5 is proprietary.
Which is newer?
Muse Spark Open is the newest, released Oct 15, 2026. Gemini 4 Argon came out Oct 13, 2026; Claude Sonnet 5.5 came out Sep 28, 2026. Knowledge cutoff: Gemini 4 Argon Mar 2026, Muse Spark Open Jan 4, 2026, Claude Sonnet 5.5 Jun 2026.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Nov 2, 2026.