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Comparison · 2 models · Updated Oct 4, 2026

Grok 4.5 vs Muse Spark 1.1

Muse Spark 1.1 comes out ahead, 70 to 64 on our weighted score, and it is the cheaper option too.

  1. xAI

    Grok 4.5

    Released Jul 8, 2026

    64/100
    • ECI154.0
    • Price$2.00 / $6.00
    • Context500K
  2. Our pick

    Meta

    Muse Spark 1.1

    Released Jul 9, 2026

    70/100
    • ECI154.3
    • Price$1.25 / $4.25
    • Context1.05M
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Muse Spark 1.1 is our pick

Muse Spark 1.1 is the better all-round choice, scoring 70/100 against Grok 4.5 (64). It leads on price, inputs & features and context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityMuse Spark 1.1Capabilities Index (ECI): Muse Spark 1.1 154.3 · Grok 4.5 154.0
  • Lowest priceMuse Spark 1.1Muse Spark 1.1 $2.00 · Grok 4.5 $3.00 per 1M tokens (3:1 blend)
  • Longest contextMuse Spark 1.1Muse Spark 1.1 1,048,576 · Grok 4.5 500,000 tokens
  • Widest inputsMuse Spark 1.1Grok 4.5: Text, Images · Muse Spark 1.1: Text, Images, PDFs, Video
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGrok 4.5Muse Spark 1.1
CapabilityCapabilities Index (ECI)50%8384
Price25%2736
Inputs & features15%7090
Context window10%4861
Overall100%64/10070/100
02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Grok 4.5 vs Muse Spark 1.1 specifications side by side
SpecificationGrok 4.5xAIMuse Spark 1.1Meta
Capability
Capabilities Index (ECI)154.0154.3 (best)
ECI rank#36 of 148#35 of 148 (best)
GPQA DiamondGraduate-level science questions93.4%—
FrontierMath Tiers 1–3Research-level mathematics57.2%—
OTIS Mock AIME 2024–2025Competition mathematics97.8%—
SimpleQA VerifiedShort factual questions48.3%57.8% (best)
Price per million tokens
Input$2.00$1.25 (best)
Output$6.00$4.25 (best)
Cached input$0.30$0.15 (best)
Blended (3:1)$3.00$2.00 (best)
Long-context rateOver 200K: $4.00 / $12.00Same rate
Price sourceOfficial xAI APIOfficial Meta API
Limits
Context window500,000 tokens1,048,576 tokens (best)
Max output500,000 tokens (best)131,072 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoNoYes
ReasoningYeslow · medium · highYesminimal · low · medium · high · xhigh
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgrok-4.5muse-spark-1.1
API providers24 (best)13
ReleasedJul 8, 2026Jul 9, 2026
Knowledge cutoff——
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Grok 4.5$32.00
  • Muse Spark 1.1$21.00
04 — Questions

Which should you choose?

Which is better: Grok 4.5 or Muse Spark 1.1?

Muse Spark 1.1 is the better all-round choice, scoring 70/100 against Grok 4.5 (64). It leads on price, inputs & features and context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Grok 4.5 or Muse Spark 1.1?

Muse Spark 1.1 is cheaper at $1.25 input / $4.25 output per million tokens (official Meta API price). Grok 4.5 costs $2.00 input / $6.00 output per million tokens (official xAI API price). At a typical mix of three input tokens to one output token, that is $2.00 per million tokens for Muse Spark 1.1 versus $3.00 for Grok 4.5 (1.5× as much).

Which scores higher on benchmarks?

Muse Spark 1.1 scores higher on the Capabilities Index (ECI): Muse Spark 1.1 154.3 (#35 of 148) and Grok 4.5 154.0 (#36 of 148). The confidence ranges of the top two overlap (152.2–157.1 vs 152.3–156.1), so treat the gap as small. On individual benchmarks: SimpleQA Verified — Muse Spark 1.1 57.8%, Grok 4.5 48.3%.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4.5 and Muse Spark 1.1 yet, so there is no like-for-like coding score. On overall capability, Muse Spark 1.1 leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

Muse Spark 1.1 has the largest context window at 1,048,576 tokens, against 500,000 for Grok 4.5. Maximum output per response: Grok 4.5 up to 500,000, Muse Spark 1.1 up to 131,072 tokens.

Which can read images, PDFs, audio or video?

Grok 4.5 accepts text and images; Muse Spark 1.1 accepts text, images, PDFs and video. Muse Spark 1.1 handles the widest range of inputs.

Are any of these open source?

No. Grok 4.5 and Muse Spark 1.1 are proprietary and only available through APIs and apps.

Which is newer?

Muse Spark 1.1 is the newest, released Jul 9, 2026. Grok 4.5 came out Jul 8, 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.