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Appen
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Long-standing provider of human-labeled, expert-validated training data and model evaluation services for building frontier AI.

1.2M visits/mo
Pricing

No public pricing

Core features
  • Frontier alignment data (RLHF, SFT, red teaming)
  • Speech and audio data
  • Multimodal / VLM annotation
  • Physical AI data (LiDAR, robotics, sensor fusion)
  • Model integrity, bias and hallucination audits
  • 1M+ vetted contributors, 500+ locales
  • SOC2 and ISO 27001 certified
Use cases
  • Source training data for AI models
  • Evaluate and benchmark models
  • Annotate multimodal and sensor data
  • Run safety and bias audits
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