---
id: "2026-02-11-ai2-molmospaces"
url: "https://postcutoff.com/e/2026-02-11-ai2-molmospaces/"
as_of: "2026-11-13T13:49:00+01:00"
date: "2026-02-11"
date_precision: day
category: benchmark
importance: 2
confidence: high
status: [Confirmed]
sources: 3
editor: human editor
human_review: null
version: "2026-10-04"
---

As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/e/2026-02-11-ai2-molmospaces/

# Ai2 launches MolmoSpaces, an open simulation ecosystem and leaderboard for generalist robot policies

On 2026-02-11 the Allen Institute for AI released MolmoSpaces, an open ecosystem of 230,000+ indoor scenes, 130,000+ object models and 42M+ annotated 6-DoF grasps usable in MuJoCo, ManiSkill and Isaac Lab/Sim, together with MolmoSpaces-Bench and a public leaderboard. The leaderboard became one of the main places labs cite for robot-policy rankings; NVIDIA claimed No. 1 for GR00T N2 on MolmoSpaces and RoboArena at GTC 2026.

## Key facts
- 230,000+ indoor scenes, 130,000+ object models (curated from Objaverse and THOR), 42M+ 6-DoF grasps over 48,000+ objects
- Simulators: MuJoCo, ManiSkill, NVIDIA Isaac Lab/Sim (via USD conversion); navigation and manipulation
- MolmoSpaces-Bench measures generalization along controlled axes (object properties, layout, task complexity, lighting/viewpoint, dynamics, instruction phrasing) instead of one success rate
- Leaderboard: molmospaces.allen.ai/leaderboard; simulation only
- Paper: arXiv 2602.11337

## What happened

Ai2 combined large-scale procedurally generated and curated 3D homes, object libraries and grasp annotations into one open robot-learning ecosystem with a standardized benchmark and leaderboard.

## Why it matters

Robot learning lacked shared benchmarks like those language models have. MolmoSpaces (simulated) and RoboArena (real-world, crowd-sourced) have become the standard leaderboards cited in 2026 model launches. Because MolmoSpaces is simulation-only, how well it predicts real-world performance is still an open question.

## Your AI and this story

- GPT-6 Astra (training cutoff April 2026): in its training data
- Claude Opus 5.5 (training cutoff June 2026): in its training data
- Gemini 4 Hydrogen (training cutoff March 2026): in its training data
- Grok 4.7 (training cutoff May 2026): in its training data

## Sources

1. [Ai2 blog: MolmoSpaces, an open ecosystem for embodied AI](https://allenai.org/blog/molmospaces) (allenai.org, official)
2. [arXiv 2602.11337: MolmoSpaces](https://arxiv.org/pdf/2602.11337) (arxiv.org, paper)
3. [MolmoSpaces leaderboard](https://molmospaces.allen.ai/leaderboard) (molmospaces.allen.ai, official)

## Changes

- 2026-09-29 (filed): Created

## Related

- 2026-05-05: [Ai2 releases MolmoAct 2, a fully open robot action-reasoning model that beats π0.5 on real-world tasks](https://postcutoff.com/e/2026-05-05-ai2-molmoact-2/index.md)
- 2026-03-16: [NVIDIA previews the GR00T N2 world action model and announces Cosmos 3 at GTC 2026](https://postcutoff.com/e/2026-03-16-nvidia-gtc-2026-robotics-groot-n2-cosmos-3/index.md)
- 2025-06-22: [RoboArena: crowd-sourced, double-blind real-world evaluation of generalist robot policies](https://postcutoff.com/e/2025-06-22-roboarena/index.md)