OpenAI

GPT-5.6 Luna

The fastest and lowest-priced GPT-5.6 tier, intended for high-volume workflows that need current agent capabilities without flagship token costs.

fastagentsefficienthigh-volume

Model record

GPT-5.6 Luna model overview

GPT-5.6 Luna is a api + app model from OpenAI. It was released on July 9, 2026. Its strongest case is lowest gpt-5.6 list price, while buyers should account for lower peak reasoning than sol and terra.

GPT-5.6 Luna benchmark snapshot

EvaluationReported scoreWhat it probes
MMLU-ProNot reportedBroad knowledge and multi-step reasoning
GPQA Diamond92.3Graduate-level science reasoning
SWE-bench VerifiedNot reportedVerified real-repository issue resolution
LiveCodeBenchNot reportedContamination-aware competitive programming
SWE-Bench Pro62.7Longer, harder professional software tasks
Artificial Analysis Intelligence Index51.2Composite third-party capability index; version matters

Scores are percentages reported by model creators or benchmark maintainers under varying settings. A blank is preferable to an inferred result. See our methodology.

GPT-5.6 Luna strengths

  • Lowest GPT-5.6 list price
  • High-volume task fit
  • Strong family-level tool support

GPT-5.6 Luna limitations

  • Lower peak reasoning than Sol and Terra
  • Closed weights
Editorial take: Benchmark rank should narrow a shortlist, not close a purchase. Run a private evaluation with representative prompts, failure cases, latency targets, and total token costs.

Compare GPT-5.6 Luna

Source record

Specifications and scores are linked to the best source located during review. Provider-reported results are not presented as third-party lab reproductions.

Read OpenAI GPT-5.6 announcement