GroundBench - 32 Vertices: leaderboard

GroundBench (Bian et al., 2026) at a budget of 32 vertices: the model traces the object named by a RefCOCO-family referring expression with exactly 32 integer vertices. Filled-region IoU with the canonical 32-vertex target contour on a 0-100 scale, counting unparseable answers as zero; higher is better.

Metric: Filled-region IoU (0-100), IoU x 100 (N=32 vertex budget; 1,500 RefCOCO, RefCOCO+ and RefCOCOg image, expression and referent triples (500 each) re-targeted to exact-N polygons; the model returns exactly N integer vertices and the filled polygon is scored by IoU against the canonical target; fixed denominator (an unparseable answer scores 0); first parseable output over one call plus up to two stateless retries). Source: arxiv.org. Saturation forecast: Around February 2027. 4 models tracked.

Top models

#ModelScoreOverall rank
1Gemini 3.5 Flash (High)57.8#98 (Gemini 3.5 Flash)
2Seed 2.0 Pro44.4#209
3Kimi K2.7 Code33.7#180

No result here: #1 Claude Fable 5.2, #2 Gemini 4 Carbon, #5 Claude Opus 5.5.

Interactive version: theaggregate.ai/benchmark?slug=groundbench-32-vertices · How It Works · Data refreshed daily, snapshot 2026-11-12.