Gemini 3.8 Flash vs Muse Spark 1.3 vs Claude Sonnet 5.5
Too close to call on our weighted score (Gemini 3.8 Flash 75, Muse Spark 1.3 73, Claude Sonnet 5.5 72). The right pick depends on what you value most.
GoogleGemini 3.8 Flash
75/100- ECI156.9
- Price$0.75 / $3.75
- Context1.05M
MetaMuse Spark 1.3
73/100- ECI156.9
- Price$1.25 / $4.25
- Context1.05M
AnthropicClaude Sonnet 5.5
72/100- ECI165.2
- Price$2.00 / $10.00
- Context1M
Too close to call
It is close. Our weighted score puts them within 2 points (Gemini 3.8 Flash 75/100, Muse Spark 1.3 73/100, Claude Sonnet 5.5 72/100), so choose by what matters most for your work: Claude Sonnet 5.5 for raw capability and Gemini 3.8 Flash on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityClaude Sonnet 5.5Capabilities Index (ECI): Claude Sonnet 5.5 165.2 · Gemini 3.8 Flash 156.9 · Muse Spark 1.3 156.9
- Lowest priceGemini 3.8 FlashGemini 3.8 Flash $1.50 · Muse Spark 1.3 $2.00 · Claude Sonnet 5.5 $4.00 per 1M tokens (3:1 blend)
- Longest contextGemini 3.8 Flash and Muse Spark 1.3Gemini 3.8 Flash 1,048,576 · Muse Spark 1.3 1,048,576 · Claude Sonnet 5.5 1,000,000 tokens
- Widest inputsGemini 3.8 Flash and Muse Spark 1.3Gemini 3.8 Flash: Text, Images, PDFs, Audio, Video · Muse Spark 1.3: Text, Images, PDFs, Audio, Video · Claude Sonnet 5.5: Text, Images, PDFs
- Self-hostingNo open weightsAll three are available only through APIs
| Measure | Weight | Gemini 3.8 Flash | Muse Spark 1.3 | Claude Sonnet 5.5 |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 87 | 87 | 97 |
| Price | 25% | 42 | 36 | 21 |
| Inputs & features | 15% | 100 | 100 | 80 |
| Context window | 10% | 61 | 61 | 60 |
| Overall | 100% | 75/100 | 73/100 | 72/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Gemini 3.8 FlashGoogle | Muse Spark 1.3Meta | Claude Sonnet 5.5Anthropic |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 156.9 | 156.9 | 165.2 (best) |
| ECI rank | #15 of 148 | #17 of 148 | #3 of 148 (best) |
| GPQA DiamondGraduate-level science questions | 95.4% | — | 95.6% (best) |
| FrontierMath Tiers 1–3Research-level mathematics | 68.4% | 74.4% | 88.8% (best) |
| OTIS Mock AIME 2024–2025Competition mathematics | 98.9% | 99.2% | 100% (best) |
| SimpleQA VerifiedShort factual questions | 69.7% (best) | — | 46.5% |
| Price per million tokens | |||
| Input | $0.75 (best) | $1.25 | $2.00 |
| Output | $3.75 (best) | $4.25 | $10.00 |
| Cached input | $0.075 (best) | $0.15 | $0.20 |
| Blended (3:1) | $1.50 (best) | $2.00 | $4.00 |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official Google API | Official Meta API | 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 | Yes | Yes |
| Audio | Yes | Yes | No |
| Video | Yes | Yes | No |
| Reasoning | Yeslow · medium · high | Yesminimal · low · medium · high · xhigh · max | Yeslow · medium · high · xhigh · max |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | Yes |
| Availability | |||
| Weights | Proprietary | Proprietary | Proprietary |
| API model ID | gemini-3.8-flash | muse-spark-1.3 | claude-sonnet-5-5 |
| API providers | 21 | 12 | 23 (best) |
| Released | Sep 2, 2026 | Sep 2, 2026 | Sep 28, 2026 |
| Knowledge cutoff | — | — | 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 3.8 Flash$15.00
- Muse Spark 1.3$21.00
- Claude Sonnet 5.5$40.00
Which should you choose?
Which is better: Gemini 3.8 Flash, Muse Spark 1.3 or Claude Sonnet 5.5?
It is close. Our weighted score puts them within 2 points (Gemini 3.8 Flash 75/100, Muse Spark 1.3 73/100, Claude Sonnet 5.5 72/100), so choose by what matters most for your work: Claude Sonnet 5.5 for raw capability and Gemini 3.8 Flash on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, Gemini 3.8 Flash, Muse Spark 1.3 or Claude Sonnet 5.5?
Gemini 3.8 Flash is cheaper at $0.75 input / $3.75 output per million tokens (official Google API price). Muse Spark 1.3 costs $1.25 input / $4.25 output per million tokens (official Meta 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 $1.50 per million tokens for Gemini 3.8 Flash versus $2.00 for Muse Spark 1.3 (1.3× as much) and $4.00 for Claude Sonnet 5.5 (2.7× as much).
Which scores higher on benchmarks?
Claude Sonnet 5.5 scores higher on the Capabilities Index (ECI): Claude Sonnet 5.5 165.2 (#3 of 148), Gemini 3.8 Flash 156.9 (#15 of 148) and Muse Spark 1.3 156.9 (#17 of 148). Their confidence ranges do not overlap (161.8–169.4 vs 154.6–160.4), so the gap is a real one. On individual benchmarks: FrontierMath Tiers 1–3 — Claude Sonnet 5.5 88.8%, Muse Spark 1.3 74.4%, Gemini 3.8 Flash 68.4%; OTIS Mock AIME 2024–2025 — Claude Sonnet 5.5 100%, Muse Spark 1.3 99.2%, Gemini 3.8 Flash 98.9%.
Which is better for coding?
There are no published SWE-bench Verified results for Gemini 3.8 Flash, Muse Spark 1.3 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 3.8 Flash and Muse Spark 1.3 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 3.8 Flash up to 65,536, Muse Spark 1.3 up to 131,072, Claude Sonnet 5.5 up to 128,000 tokens.
Which can read images, PDFs, audio or video?
Gemini 3.8 Flash accepts text, images, PDFs, audio and video; Muse Spark 1.3 accepts text, images, PDFs, audio and video; Claude Sonnet 5.5 accepts text, images and PDFs. Gemini 3.8 Flash handles the widest range of inputs.
Are any of these open source?
No. Gemini 3.8 Flash, Muse Spark 1.3 and Claude Sonnet 5.5 are proprietary and only available through APIs and apps.
Which is newer?
Claude Sonnet 5.5 is the newest, released Sep 28, 2026. Gemini 3.8 Flash came out Sep 2, 2026; Muse Spark 1.3 came out Sep 2, 2026. Knowledge cutoff: 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 Oct 4, 2026.
