Artificial intelligence · July 2026

GPT-5.6

Three tiers, Sol, Terra and Luna, after a government-restricted preview.

OpenAI released GPT-5.6 in three sizes after a limited preview on June 26, 2026 under government restrictions. The top tier, Sol, used 54% fewer tokens on coding tasks than its predecessor.

See it in the living tree Wikipedia Source

Arcs above join it to what it stood on, arcs below to what it led to. The bar places this stretch on the tree's whole timeline.

What it built on 1

GPT-5.5 2026

What it led to 2

Cycle double cover proof 2026
GPT-6 Astra 2026

Related measurements

The dashed line marks when it first worked.

Best AI score on GPQA Diamond Latest: 95.8 % correct (2026) Source: Epoch AI, Capabilities & benchmarking (benchmark_data.zip, gpqa_diamond.csv); Anthropic: Claude 3 public launch (March 4, 2024)

Training compute of notable AI models Source: Epoch AI, Notable AI Models (CC BY 4.0)