Labelbox review: expert signal and RL environments for AI training data
Answer in brief: Labelbox is a strong buy-route pick for expert preference data and RL environments, with the tooling heritage to support label work as well. Its Alignerr network lists 2.6M+ contributors, including 50K+ PhDs and 85K+ licensed professionals. Horizon supplies RL environments and evals, and Terra covers robotics data. It is SOC 2 Type II certified and freshly funded.
Expert judgment, delivered as training signal. Preference pairs, ranked trajectories and rubric-graded assessments, in formats ready for your pipeline.
Independent research, checked against Labelbox's official site on 2026-11-09. We have not tested the service.
Where Labelbox fits in the five routes
Buy: Alignerr experts write rubrics, preferences and graded assessments. Horizon builds RL environments and evals for reasoning, tool use and computer use, including WorldSim enterprise simulations. Collect: Terra captures egocentric and teleoperated robotics demonstrations on purpose-built rigs. Label: its long history as labeling software. For robotics depth, see Best robotics data companies.
Who it fits
- Labs that need expert preference data across many domains and languages.
- Teams building agents that need RL environments and evals.
- Buyers who need SOC 2 Type II security and NDAs.
Strengths
- Network scale: 2.6M+ contributors, 50K+ PhDs, 200K+ master's degrees, 85K+ licensed professionals, 40+ countries, 75+ languages and 200+ domains (Labelbox's figures).
- Continuous calibration: contributors are skill-tested and their performance is monitored against ground truth.
- Published customer work: stories with Meta (the GIM benchmark), Google Cloud (Vertex AI) and Intuitive Surgical.
- Fresh capital: a $100M+ Series E announced on October 14, 2026, led by Infinitum Partners at a $1.25B pre-money valuation. The total combines equity and a credit facility.
Honest drawbacks
- Its focus is spreading: the homepage now leads with Recursion, an agent product for engineering teams.
- Labelbox did not disclose how the Series E splits between equity and credit.
- No public pricing for data services.
Pricing model
Custom quotes through sales.
Best alternatives
- Mercor: credentialed professional experts.
- Scale AI: the broadest labeling and physical-AI engine.
- iMerit: managed labeling plus Ango Hub.
FAQ
What is Alignerr?
Labelbox's expert network. It lists 2.6M+ contributors across 200+ domains and delivers expert judgment as training and evaluation signal.
How much did Labelbox raise in its Series E?
More than $100M, combining equity and a credit facility, announced on October 14, 2026 at a $1.25B pre-money valuation.
Is Labelbox SOC 2 certified?
Yes. Labelbox says it is SOC 2 Type II certified.
Sources
- labelbox.com
- Alignerr
- Labelbox Series E announcement
- PR Newswire (2026-10-14)
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