Is GPT-6 Astra a good deal?

Whether anything in this catalogue beats GPT-6 Astra on both quality and price, and what you give up if it does. A computation on the current catalogue, not an opinion.

6 undominated of 137 · Sep 19, 2026

As of Sep 19, 2026, GPT-6 Astra is dominated for Balanced on LMArena. GPT-5.5 scores 21.9 higher and costs 44% less, with a covering envelope. 6 of 137 rated, priced standard models are undominated.

Current model

GPT-6 Astra

Balanced

3 tokens in per 1 out

GPT-5.51465.6 · $11.25/MGPT-6 Astra1443.7 · $20.00/MLMArena EloEffective $/M · Balanced
137 rated, priced standard models. Chartreuse is the frontier. Cobalt is the model you named, when it is not on the staircase.

GPT-5.5 is both better and cheaper than GPT-6 Astra: 21.9 points higher on LMArena and 44% less per million tokens, $8.75 cheaper at this mix.

GPT-6 Astra

LMArena Elo

1443.7

Effective $/M · Balanced

$20.00/M

GPT-5.5

LMArena Elo

1465.6

Effective $/M · Balanced

$11.25/M

GPT-6 Astra takes file, image, text, returns up to 128,000 tokens from a 1,050,000-token context, and is listed by 5 sellers.

Compared against 137 rated, priced models on this lens: 4 models dominate it and give up nothing, 5 more dominate it but give something up. GPT-6 Astra scores 1443.7 at $20.00 per million tokens for this mix.

Envelope-safe replacements

Each row scores at least as high, costs no more, and covers this model’s context, output, modalities, tools, and reasoning. A cheaper narrower model is not listed here.

ModelLMArenaEffective $/MYou save
GPT-5.51465.6 +21.9$11.25/M44%
GPT-5.6 Sol1455.1 +11.4$4.00/M80%
GPT-5.41452.6 +8.9$5.63/M72%
GPT-5.6 Terra1446.2 +2.5$4.50/M78%

Higher score, lower price, named losses

Not a drop-in. The loss is why these are not a recommendation.

ModelLMArenaEffective $/MYou give up
Claude Fable 5.11507.6$20.00/Mcontext
Claude Opus 51504.9$10.00/Mcontext
Claude Opus 4.61503.0$10.00/Mcontext
Gemini 3.8 Flash1494.7$1.50/Mcontext, max output
Claude Fable 51492.6$20.00/Mcontext

Open the frontier

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