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Prolific logo
Prolific
✓ verifiedPaid

Research participant marketplace that gives AI teams and academics fast access to verified, screened human data and feedback.

21M visits/mo
Outlier AI logo
Outlier AI
✓ verifiedFree

Outlier is a platform where experts earn freelance income training and evaluating AI by writing prompts, rubrics and rating answers.

12M visits/mo
SourceBae logo
SourceBae
✓ verifiedFree

Marketplace connecting paid domain-expert contractors to AI labs for data labeling, RLHF and model evaluation work.

29K visits/mo
Zara, by micro1 logo
Zara, by micro1
✓ verifiedPaid

Data lab providing expert human data, RL environments, and contextual evaluations to train and assess AI models and agents.

6.3M visits/mo45K saves
Pricing

No public pricing

No public pricing

No public pricing

No public pricing

Core features
  • 300,000+ verified, screened participants
  • 300+ audience targeting filters
  • Representative and quota-based sampling
  • API and no-code survey tool integrations
  • AI-powered participant quality monitoring (Protocol)
  • Managed services with dedicated project teams
  • Access to vetted domain experts
  • Remote AI-training gig work
  • Tasks: prompt writing, rubrics, rating answers
  • Flexible hours, work from anywhere
  • Weekly, quality-based pay
  • Roles across coding, STEM and languages
  • Free access to paid AI models
  • Data annotation and multi-format labeling
  • RLHF and human preference feedback
  • AI model red-teaming and safety testing
  • On-demand vetted ML/prompt engineering talent
  • Synthetic data generation
  • Structured model evaluation and benchmarking
  • Realm: RL environments and frontier evaluations
  • Cortex: contextual evaluation for production AI agents
  • Expert-demonstrated robotics training data
  • Benchmarks such as LongExtractionBench
  • Expert human data partnerships
  • Research lab on human data markets
Use cases
  • Collecting human preference data for RLHF or model evaluation
  • Running academic behavioral or market research studies
  • Sourcing domain-expert data for specialized AI benchmarks
  • Earning side income as an AI trainer
  • Contributing expertise to improve AI
  • Flexible remote work for grads and experts
  • Gaining hands-on AI and prompt experience
  • AI labs sourcing domain experts for RLHF projects
  • Companies needing red-teaming of a new model
  • Teams building custom labeled training datasets
  • Domain experts (healthcare, legal, finance) earning remote pay for AI training work
  • Train and evaluate frontier AI models
  • Improve agent performance in production
  • Source expert human data for AI labs
  • Gather demonstration data for robotics
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