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Comparison · 2 models · Updated Oct 4, 2026

GPT-6 Astra vs GPT-6 Astra (Fast)

Too close to call on our weighted score (GPT-6 Astra 36, GPT-6 Astra (Fast) 36). The right pick depends on what you value most.

  1. OpenAI

    GPT-6 Astra

    Released Sep 4, 2026

    36/100
    • ECI166.5
    • Price$10.00 / $50.00
    • Context1.05M
  2. OpenAI

    GPT-6 Astra (Fast)

    Released Sep 4, 2026

    36/100
    • ECI—
    • Price$20.00 / $100.00
    • Context1.05M
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01 — Verdict

Too close to call

It is close. Our weighted score puts them within a point (GPT-6 Astra 36/100, GPT-6 Astra (Fast) 36/100), so choose by what matters most for your work: GPT-6 Astra on price. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest priceGPT-6 AstraGPT-6 Astra $20.00 · GPT-6 Astra (Fast) $40.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameGPT-6 Astra 1,050,000 · GPT-6 Astra (Fast) 1,050,000 tokens
  • Widest inputsSame inputsGPT-6 Astra: Text, Images, PDFs · GPT-6 Astra (Fast): Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-6 AstraGPT-6 Astra (Fast)
Price50%00
Inputs & features30%8080
Context window20%6161
Overall100%36/10036/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

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

GPT-6 Astra vs GPT-6 Astra (Fast) specifications side by side
SpecificationGPT-6 AstraOpenAIGPT-6 Astra (Fast)OpenAI
Capability
Capabilities Index (ECI)166.5—
ECI rank#2 of 148—
GPQA DiamondGraduate-level science questions95.8%—
FrontierMath Tiers 1–3Research-level mathematics93.7%—
OTIS Mock AIME 2024–2025Competition mathematics100%—
SimpleQA VerifiedShort factual questions75.6%—
Price per million tokens
Input$10.00 (best)$20.00
Output$50.00 (best)$100.00
Cached input$1.00—
Blended (3:1)$20.00 (best)$40.00
Long-context rateOver 272K: $20.00 / $75.00Same rate
Price sourceOfficial OpenAI APIMedian of 1 providers
Limits
Context window1,050,000 tokens1,050,000 tokens
Max output128,000 tokens128,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesYes
AudioNoNo
VideoNoNo
ReasoningYeslow · medium · high · xhigh · maxYes
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgpt-6-astra—
API providers26 (best)1
ReleasedSep 4, 2026Sep 4, 2026
Knowledge cutoffApr 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.

  • GPT-6 Astra$200.00
  • GPT-6 Astra (Fast)$400.00
04 — Questions

Which should you choose?

Which is better: GPT-6 Astra or GPT-6 Astra (Fast)?

It is close. Our weighted score puts them within a point (GPT-6 Astra 36/100, GPT-6 Astra (Fast) 36/100), so choose by what matters most for your work: GPT-6 Astra on price. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, GPT-6 Astra or GPT-6 Astra (Fast)?

GPT-6 Astra is cheaper at $10.00 input / $50.00 output per million tokens (official OpenAI API price). GPT-6 Astra (Fast) costs $20.00 input / $100.00 output per million tokens (median across 1 API provider). At a typical mix of three input tokens to one output token, that is $20.00 per million tokens for GPT-6 Astra versus $40.00 for GPT-6 Astra (Fast) (2× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. GPT-6 Astra has an ECI of 166.5 and GPT-6 Astra (Fast) has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-6 Astra and GPT-6 Astra (Fast) yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

GPT-6 Astra and GPT-6 Astra (Fast) share the same 1,050,000-token context window. Maximum output per response: GPT-6 Astra up to 128,000, GPT-6 Astra (Fast) up to 128,000 tokens.

Which can read images, PDFs, audio or video?

GPT-6 Astra accepts text, images and PDFs; GPT-6 Astra (Fast) accepts text, images and PDFs. They handle the same number of input types.

Are any of these open source?

No. GPT-6 Astra and GPT-6 Astra (Fast) are proprietary and only available through APIs and apps.

Which is newer?

GPT-6 Astra is the newest, released Sep 4, 2026. GPT-6 Astra (Fast) came out Sep 4, 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.