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Comparison · 2 models · Updated Nov 2, 2026

GPT-6 Astra (Fast) vs Hy4 preview

Hy4 preview comes out ahead, 44 to 33 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    GPT-6 Astra (Fast)

    Released Sep 4, 2026New

    33/100
    • ECI—
    • Price$20.00 / $100.00
    • Context1.05M
  2. Our pick

    Tencent

    Hy4 preview

    Released Aug 28, 2026

    44/100
    • ECI—
    • Price$0.834 / $2.50
    • Context1.02M
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01 — Verdict

Hy4 preview is our pick

Hy4 preview is the better all-round choice, scoring 44/100 against GPT-6 Astra (Fast) (33). It leads on price. GPT-6 Astra (Fast) wins on inputs & features. 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 priceHy4 previewHy4 preview $1.25 · GPT-6 Astra (Fast) $40.00 per 1M tokens (3:1 blend)
  • Longest contextGPT-6 Astra (Fast)GPT-6 Astra (Fast) 1,050,000 · Hy4 preview 1,024,000 tokens
  • Widest inputsGPT-6 Astra (Fast)GPT-6 Astra (Fast): Text, Images, PDFs · Hy4 preview: Text
  • Self-hostingHy4 previewPublishes downloadable weights
How the score is built
MeasureWeightGPT-6 Astra (Fast)Hy4 preview
Price50%043
Inputs & features30%7035
Context window20%6160
Overall100%33/10044/100

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 (Fast) vs Hy4 preview specifications side by side
SpecificationGPT-6 Astra (Fast)OpenAIHy4 previewTencent
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$20.00$0.834 (best)
Output$100.00$2.50 (best)
Cached input—$0.042
Blended (3:1)$40.00$1.25 (best)
Long-context rateSame rateSame rate
Price sourceMedian of 1 providersOfficial Tencent TokenHub API
Limits
Context window1,050,000 tokens (best)1,024,000 tokens
Max output128,000 tokens (best)64,000 tokens
Inputs and features
TextYesYes
ImagesYesNo
PDFsYesNo
AudioNoNo
VideoNoNo
ReasoningYesYeshigh
Tool callingYesYes
Structured outputNoNo
Availability
WeightsProprietaryOpen
API model ID—hy4-preview
API providers117 (best)
ReleasedSep 4, 2026Aug 28, 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.

  • GPT-6 Astra (Fast)$400.00
  • Hy4 preview$13.34
04 — Questions

Which should you choose?

Which is better: GPT-6 Astra (Fast) or Hy4 preview?

Hy4 preview is the better all-round choice, scoring 44/100 against GPT-6 Astra (Fast) (33). It leads on price. GPT-6 Astra (Fast) wins on inputs & features. 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 (Fast) or Hy4 preview?

Hy4 preview is cheaper at $0.834 input / $2.50 output per million tokens (official Tencent TokenHub 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 $1.25 per million tokens for Hy4 preview versus $40.00 for GPT-6 Astra (Fast) (32× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. GPT-6 Astra (Fast) has not been scored yet and Hy4 preview has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-6 Astra (Fast) and Hy4 preview 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 (Fast) has the largest context window at 1,050,000 tokens, against 1,024,000 for Hy4 preview. Maximum output per response: GPT-6 Astra (Fast) up to 128,000, Hy4 preview up to 64,000 tokens.

Which can read images, PDFs, audio or video?

GPT-6 Astra (Fast) accepts text, images and PDFs; Hy4 preview accepts text. GPT-6 Astra (Fast) handles the widest range of inputs.

Are any of these open source?

Hy4 preview publishes its weights and can be self-hosted; GPT-6 Astra (Fast) is proprietary.

Which is newer?

GPT-6 Astra (Fast) is the newest, released Sep 4, 2026. Hy4 preview came out Aug 28, 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 Nov 2, 2026.