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Comparison · 2 models · Updated Oct 4, 2026

Muse Spark 1.3 vs GPT-6 Astra

Muse Spark 1.3 comes out ahead, 73 to 68 on our weighted score, and it is the cheaper option too.

  1. Our pick

    Meta

    Muse Spark 1.3

    Released Sep 2, 2026

    73/100
    • ECI156.9
    • Price$1.25 / $4.25
    • Context1.05M
    Full specs Remove Muse Spark 1.3

  2. OpenAI

    GPT-6 Astra

    Released Sep 4, 2026

    68/100
    • ECI166.5
    • Price$10.00 / $50.00
    • Context1.05M
    Full specs Remove GPT-6 Astra

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Muse Spark 1.3 is our pick

Muse Spark 1.3 is the better all-round choice, scoring 73/100 against GPT-6 Astra (68). It leads on price and inputs & features. GPT-6 Astra wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGPT-6 AstraCapabilities Index (ECI): GPT-6 Astra 166.5 · Muse Spark 1.3 156.9
  • Lowest priceMuse Spark 1.3Muse Spark 1.3 $2.00 · GPT-6 Astra $20.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameGPT-6 Astra 1,050,000 · Muse Spark 1.3 1,048,576 tokens
  • Widest inputsMuse Spark 1.3Muse Spark 1.3: Text, Images, PDFs, Audio, Video · GPT-6 Astra: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightMuse Spark 1.3GPT-6 Astra
CapabilityCapabilities Index (ECI)50%8799
Price25%360
Inputs & features15%10080
Context window10%6161
Overall100%73/10068/100
02 — Side by side

Every spec in one table

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

Muse Spark 1.3 vs GPT-6 Astra specifications side by side
SpecificationMuse Spark 1.3MetaGPT-6 AstraOpenAI
Capability
Capabilities Index (ECI)156.9166.5 (best)
ECI rank#17 of 148#2 of 148 (best)
GPQA DiamondGraduate-level science questions—95.8%
FrontierMath Tiers 1–3Research-level mathematics74.4%93.7% (best)
OTIS Mock AIME 2024–2025Competition mathematics99.2%100% (best)
SimpleQA VerifiedShort factual questions—75.6%
Price per million tokens
Input$1.25 (best)$10.00
Output$4.25 (best)$50.00
Cached input$0.15 (best)$1.00
Blended (3:1)$2.00 (best)$20.00
Long-context rateSame rateOver 272K: $20.00 / $75.00
Price sourceOfficial Meta APIOfficial OpenAI API
Limits
Context window1,048,576 tokens1,050,000 tokens (best)
Max output131,072 tokens (best)128,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesYes
AudioYesNo
VideoYesNo
ReasoningYesminimal · low · medium · high · xhigh · maxYeslow · medium · high · xhigh · max
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDmuse-spark-1.3gpt-6-astra
API providers1226 (best)
ReleasedSep 2, 2026Sep 4, 2026
Knowledge cutoff—Apr 30, 2026
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.

  • Muse Spark 1.3$21.00
  • GPT-6 Astra$200.00
04 — Questions

Which should you choose?

Which is better: Muse Spark 1.3 or GPT-6 Astra?

Muse Spark 1.3 is the better all-round choice, scoring 73/100 against GPT-6 Astra (68). It leads on price and inputs & features. GPT-6 Astra wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Muse Spark 1.3 or GPT-6 Astra?

Muse Spark 1.3 is cheaper at $1.25 input / $4.25 output per million tokens (official Meta API price). GPT-6 Astra costs $10.00 input / $50.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $2.00 per million tokens for Muse Spark 1.3 versus $20.00 for GPT-6 Astra (10× as much).

Which scores higher on benchmarks?

GPT-6 Astra scores higher on the Capabilities Index (ECI): GPT-6 Astra 166.5 (#2 of 148) and Muse Spark 1.3 156.9 (#17 of 148). Their confidence ranges do not overlap (163.1–171.1 vs 154.7–159.6), so the gap is a real one. On individual benchmarks: FrontierMath Tiers 1–3 — GPT-6 Astra 93.7%, Muse Spark 1.3 74.4%; OTIS Mock AIME 2024–2025 — GPT-6 Astra 100%, Muse Spark 1.3 99.2%.

Which is better for coding?

There are no published SWE-bench Verified results for Muse Spark 1.3 and GPT-6 Astra yet, so there is no like-for-like coding score. On overall capability, GPT-6 Astra 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?

Their context windows are effectively the same size: Muse Spark 1.3 1,048,576 and GPT-6 Astra 1,050,000 tokens. Maximum output per response: Muse Spark 1.3 up to 131,072, GPT-6 Astra up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Muse Spark 1.3 accepts text, images, PDFs, audio and video; GPT-6 Astra accepts text, images and PDFs. Muse Spark 1.3 handles the widest range of inputs.

Are any of these open source?

No. Muse Spark 1.3 and GPT-6 Astra are proprietary and only available through APIs and apps.

Which is newer?

GPT-6 Astra is the newest, released Sep 4, 2026. Muse Spark 1.3 came out Sep 2, 2026. Knowledge cutoff: GPT-6 Astra Apr 30, 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.

05 — Keep comparing

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