Labelbox review: an AI training data provider for expert signal and RL environments
Answer in brief: Labelbox is our #5 AI training data provider for labs. It combines software with managed expert data. Alignerr supplies preference pairs, ranked trajectories and rubric-graded assessments from 2.6M+ contributors across 200+ domains, by Labelbox's count. Horizon supplies RL environments and evals for reasoning, tool use and computer use. Published customer stories include Meta and Google Cloud, and it recently raised a $100M+ Series E. The drawbacks are a fast-widening product line and no public price list.
Bottom line: For a lab that wants credential-filtered expert signal and agent environments from one vendor, Labelbox is a strong pick.
This is independent research based on Labelbox's site, read on 2026-11-09. We did not test the service.
What Labelbox supplies to AI labs
Labelbox describes itself as building the environments frontier labs train AI on. For labs, the relevant products are Alignerr, for expert judgment as a training signal, and Horizon, for post-training RL environments and evals. Alignerr routes each task to contributors whose credentials match the work, calibrates them against ground truth, and delivers outputs in formats ready for RLHF and RL pipelines.
An expert network with real depth
- 2.6M+ contributors, 50K+ PhDs, 200K+ master's degrees and 85K+ licensed professionals, by Labelbox's figures.
- 40+ countries, 75+ languages and 200+ professional domains, from quantitative finance and cybersecurity to medicine and formal mathematics.
- Filters for domain, credentials, experience, language, geography and past performance.
- SOC 2 Type II certified, with NDAs and data-handling protocols.
Proof points
- Meta built its GIM benchmark for evaluating frontier reasoning with Labelbox data.
- Google Cloud uses Labelbox human preference signal to evaluate LLMs inside Vertex AI.
- Labelbox publishes research such as EchoChain, an audio reasoning benchmark, and work on flaws in AI safety datasets.
Who Labelbox fits
- Labs that need multilingual, credential-filtered preference and rubric data.
- Teams training agents on computer use and tool use.
- Buyers who want software and managed services from one vendor.
Honest drawbacks
- The homepage now leads with Recursion, an agent product, which can blur the data offer.
- Labelbox's /pricing/ page returned 404 on 2026-11-09, and we found no public price list.
- Network figures are self-reported.
Pricing model
Sales-led. Contact Labelbox sales with your job scope.
Best alternatives to Labelbox
- Handshake AI: a larger network, but U.S.-only fellows.
- Toloka: agent environments plus a self-service platform.
- micro1: expert data plus Realm RL environments.
For Labelbox's Terra robotics data, compare vendors on bestroboticsdataproviders.com.
Labelbox FAQ
What is Alignerr?
Alignerr is Labelbox's expert network. It captures expert judgment as structured training signal, such as preference pairs, ranked trajectories and rubric-graded assessments.
Does Labelbox publish pricing?
No. Its /pricing/ page returned 404 when we checked on 2026-11-09, and pricing is handled through sales.
Is Labelbox SOC 2 certified?
Labelbox says Alignerr is SOC 2 Type II certified.
Sources
- Labelbox homepage
- Labelbox Alignerr
- Labelbox Series E announcement
- Labelbox: Meta GIM story
- Labelbox: Google Cloud LLM evaluation
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