GPT 5.5 Pro Pre Release

released 2026-04-23

BenchAtlas Index

as of 2026-07-14

Not enough benchmark coverage for a composite score (needs ≥4 families across ≥3 categories). The per-benchmark evidence below stands on its own — sparse coverage is an evidence gap, not a low score.

Benchmark evidence

9 results

external indices

ECI	xhigh effort	160.7 points	independent	Epoch AI Benchmarking Hub
ECI	high effort	160.7 points	independent	Epoch AI Benchmarking Hub

factuality

SimpleQA Verified

xhigh effort

64.5 %

independent

Epoch AI Benchmarking Hub

2026-04-24

knowledge science

GPQA Diamond

xhigh effort

93.9 %

independent

Epoch AI Benchmarking Hub

2026-04-24

reasoning math

FrontierMath	high effort	52.4 %	independent	Epoch AI Benchmarking Hub 2026-04-23
FrontierMath	xhigh effort	51.0 %	independent	Epoch AI Benchmarking Hub 2026-04-23
FrontierMath Tier 4older version	xhigh effort	39.6 %	independent	Epoch AI Benchmarking Hub 2026-04-23
FrontierMath Tier 4older version	high effort	39.6 %	independent	Epoch AI Benchmarking Hub 2026-04-23
OTIS Mock AIME 2024–2025	xhigh effort	100.0 %	independent	Epoch AI Benchmarking Hub 2026-04-24