WhichAI / Compare / Grok 4.5 vs GPT-5.6 Terra

Grok 4.5vsGPT-5.6 Terra

GPT-5.6 Terra scores higher on the September 8, 2026 index. Full context below: price, context window, strengths and honest limits. Verified September 8, 2026.

Grok 4.5

GPT-5.6 Terra

Provider

AA index

55.8

56.6

Released

2026-07-08

2026-07-09

Context

n/a

Price $/1M

$2 / $6

$2.5 / $15

Access

Released July 8, 2026 · API $2/$6 per 1M tokens · in Grok Build & Cursor · not yet in the EU

Released July 9, 2026 · API $2.50/$15 per 1M tokens

n/a = not published or not yet verified. Scores marked ~ are WhichAI estimates and should not be compared 1:1 with measured scores.

In one line each

Grok 4.5: xAI's first model built specifically for coding and agents: a 1.5T-parameter base trained on real Cursor sessions, at a fraction of flagship prices. Note before you commit: EU availability is still pending.

GPT-5.6 Terra: The balanced tier of the GPT-5.6 family - GPT-5.5-level quality at half the price. On track to become the everyday ChatGPT default.

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