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Comparison · 3 models · Updated Oct 4, 2026

Grok 4.20 (Reasoning) vs Muse Spark 1.1 vs Kimi K2.6

Too close to call on our weighted score (Muse Spark 1.1 70, Grok 4.20 (Reasoning) 68, Kimi K2.6 65). The right pick depends on what you value most.

  1. xAI

    Grok 4.20 (Reasoning)

    Released Mar 9, 2026

    68/100
    • ECI152.0
    • Price$1.25 / $2.50
    • Context1M
  2. Meta

    Muse Spark 1.1

    Released Jul 9, 2026

    70/100
    • ECI154.3
    • Price$1.25 / $4.25
    • Context1.05M
  3. Moonshot AI

    Kimi K2.6

    Released Apr 21, 2026

    65/100
    • ECI151.1
    • Price$0.95 / $4.00
    • Context262K
01 — Verdict

Too close to call

It is close. Our weighted score puts them within 2 points (Muse Spark 1.1 70/100, Grok 4.20 (Reasoning) 68/100, Kimi K2.6 65/100), so choose by what matters most for your work: Muse Spark 1.1 for raw capability and Grok 4.20 (Reasoning) on price. 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 4.20 (Reasoning) 152.0 · Kimi K2.6 151.1
  • Lowest priceGrok 4.20 (Reasoning)Grok 4.20 (Reasoning) $1.56 · Kimi K2.6 $1.71 · Muse Spark 1.1 $2.00 per 1M tokens (3:1 blend)
  • Longest contextMuse Spark 1.1Muse Spark 1.1 1,048,576 · Grok 4.20 (Reasoning) 1,000,000 · Kimi K2.6 262,144 tokens
  • Widest inputsMuse Spark 1.1Grok 4.20 (Reasoning): Text, Images, PDFs · Muse Spark 1.1: Text, Images, PDFs, Video · Kimi K2.6: Text, Images, Video
  • Self-hostingKimi K2.6Publishes downloadable weights
How the score is built
MeasureWeightGrok 4.20 (Reasoning)Muse Spark 1.1Kimi K2.6
CapabilityCapabilities Index (ECI)50%818479
Price25%413639
Inputs & features15%809080
Context window10%606137
Overall100%68/10070/10065/100
02 — Side by side

Every spec in one table

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

Grok 4.20 (Reasoning) vs Muse Spark 1.1 vs Kimi K2.6 specifications side by side
SpecificationGrok 4.20 (Reasoning)xAIMuse Spark 1.1MetaKimi K2.6Moonshot AI
Capability
Capabilities Index (ECI)152.0154.3 (best)151.1
ECI rank#41 of 148#35 of 148 (best)#45 of 148
GPQA DiamondGraduate-level science questions89.3%—90.8% (best)
FrontierMath Tiers 1–3Research-level mathematics44.9%—57.2% (best)
OTIS Mock AIME 2024–2025Competition mathematics92.2%—96.1% (best)
SWE-bench VerifiedFixing real GitHub issues——76.7%
SimpleQA VerifiedShort factual questions30.2%57.8% (best)34.9%
Price per million tokens
Input$1.25$1.25$0.95 (best)
Output$2.50 (best)$4.25$4.00
Cached input$0.20$0.15 (best)$0.16
Blended (3:1)$1.56 (best)$2.00$1.71
Long-context rateOver 200K: $2.50 / $5.00Same rateSame rate
Price sourceOfficial xAI APIOfficial Meta APIOfficial Moonshot AI API
Limits
Context window1,000,000 tokens1,048,576 tokens (best)262,144 tokens
Max output30,000 tokens131,072 tokens262,144 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesYesNo
AudioNoNoNo
VideoNoYesYes
ReasoningYesYesminimal · low · medium · high · xhighYes
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryOpen
API model IDgrok-4.20-0309-reasoningmuse-spark-1.1kimi-k2.6
API providers111346 (best)
ReleasedMar 9, 2026Jul 9, 2026Apr 21, 2026
Knowledge cutoff——Jan 2025
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 4.20 (Reasoning)$17.50
  • Muse Spark 1.1$21.00
  • Kimi K2.6$17.50
04 — Questions

Which should you choose?

Which is better: Grok 4.20 (Reasoning), Muse Spark 1.1 or Kimi K2.6?

It is close. Our weighted score puts them within 2 points (Muse Spark 1.1 70/100, Grok 4.20 (Reasoning) 68/100, Kimi K2.6 65/100), so choose by what matters most for your work: Muse Spark 1.1 for raw capability and Grok 4.20 (Reasoning) on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Grok 4.20 (Reasoning), Muse Spark 1.1 or Kimi K2.6?

Grok 4.20 (Reasoning) is cheaper at $1.25 input / $2.50 output per million tokens (official xAI API price). Kimi K2.6 costs $0.95 input / $4.00 output per million tokens (official Moonshot AI API price); Muse Spark 1.1 costs $1.25 input / $4.25 output per million tokens (official Meta API price). At a typical mix of three input tokens to one output token, that is $1.56 per million tokens for Grok 4.20 (Reasoning) versus $1.71 for Kimi K2.6 (1.1× as much) and $2.00 for Muse Spark 1.1 (1.3× 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), Grok 4.20 (Reasoning) 152.0 (#41 of 148) and Kimi K2.6 151.1 (#45 of 148). The confidence ranges of the top two overlap (152.2–157.1 vs 149.3–154.4), so treat the gap as small. On individual benchmarks: SimpleQA Verified — Muse Spark 1.1 57.8%, Kimi K2.6 34.9%, Grok 4.20 (Reasoning) 30.2%.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4.20 (Reasoning) 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. All three 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 1,000,000 for Grok 4.20 (Reasoning) and 262,144 for Kimi K2.6. Maximum output per response: Grok 4.20 (Reasoning) up to 30,000, Muse Spark 1.1 up to 131,072, Kimi K2.6 up to 262,144 tokens.

Which can read images, PDFs, audio or video?

Grok 4.20 (Reasoning) accepts text, images and PDFs; Muse Spark 1.1 accepts text, images, PDFs and video; Kimi K2.6 accepts text, images and video. Muse Spark 1.1 handles the widest range of inputs.

Are any of these open source?

Kimi K2.6 publishes its weights and can be self-hosted; Grok 4.20 (Reasoning) and Muse Spark 1.1 is proprietary.

Which is newer?

Muse Spark 1.1 is the newest, released Jul 9, 2026. Kimi K2.6 came out Apr 21, 2026; Grok 4.20 (Reasoning) came out Mar 9, 2026. Knowledge cutoff: Kimi K2.6 Jan 2025.

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.