Based only on the facts in our directory. The right pick still depends on the job you need done.
Lower starting price
Not comparable
Not comparable: Labelbox does not list a price
Free plan
Labelbox
Only Labelbox has one
Higher rating
Tie
4.1 against 4.1
Same job?
Yes
Both are AI Infrastructure & Agent Tooling tools
Side by side
Compared on
Labelbox
Mercor
Our rating
4.1
4.1
Starts at
Free
Not listed
Free plan
YesBetter
No
Category
AI Infrastructure & Agent Tooling
AI Infrastructure & Agent Tooling
Plans
Free
See pricing
Key features
Three connected products: Catalog (curation), Annotate (labeling), Model (evaluation)
Reinforcement-learning data factory positioning for frontier model training
Human- and model-assisted labeling workflows in one pipeline
Labelbox Unit (LBU) pricing scales by the type of data work performed
Free tier with usage caps for evaluating the platform
Marketplace matching AI labs with vetted domain experts, not generalist crowdworkers
Pool of roughly 300,000 professionals across engineering, medicine, law, and other fields
Built for reinforcement-learning feedback and evaluation work, not just raw labeling
30% recruiting fee model scales with contracted expert labor
$350M Series C at a $10 billion valuation
Pros
Full pipeline (curate, label, evaluate) avoids stitching together separate point tools
LBU pricing ties cost directly to the type of work performed rather than a flat per-seat fee
Proven at frontier-model scale with major AI labs as customers
Domain-expert focus fits specialized training data needs generalist labeling vendors can't serve
Rapid valuation growth signals strong demand from frontier AI labs
Recruiting-fee model aligns pricing directly with the caliber of expert engaged
Cons
LBU-based pricing takes time to model accurately before committing to a budget
Built for large-scale data operations, likely more infrastructure than a small team needs
Three-product scope (Catalog, Annotate, Model) adds a learning curve versus a single-purpose labeling tool
Recruiting-fee pricing model means costs scale unpredictably with expert seniority and volume
Built for AI labs at training scale, not a fit for smaller one-off labeling projects
Expert-marketplace model depends on the quality of Mercor's own vetting, which is not independently auditable by customers
Company
Labelbox, founded 2018
Mercor, founded 2023
Prices come from each vendor's pricing page, last checked 20260716. Check the vendor before you buy.
FAQ
Questions people ask
Is Labelbox better than Mercor?
In our reviews Labelbox scores 4.1 and Mercor scores 4.1. The better pick depends on the job. Labelbox: Runs reinforcement-learning data factories that power frontier models for the world's top AI labs. Mercor: Reached a $10 billion valuation organizing 300,000 human experts to train frontier AI models.
Labelbox
Mercor
