OECD Dark Pattern Harm Taxonomy

Overview

The Organization for Economic Cooperation and Development framework classifies dark pattern harms across six dimensions, providing a structured way to assess the impact of manipulative interface design.

The Six Harm Categories

H1 — Harm to User Autonomy Compromises user agency by forcing choices users wouldn’t otherwise make, limiting available options, or obfuscating the decision-making process.

H2 — Financial Loss Manipulates users into unnecessary purchases or overspending through interface design.

H3 — Privacy Harms Induces users to share excessive personal information without full understanding, elevating their risk exposure.

H4 — Psychological Detriment and Time Loss Places emotional and cognitive strain on users, exploits vulnerabilities, or wastes user time.

H5 — Weaker or Distorted Competition Prevents or dissuades users from comparison shopping, distorting market dynamics.

H6 — Reduced Consumer Trust and Engagement Erodes trust through deception about information sharing or spending, particularly when users later discover the manipulation.

When to Use This Framework

  • Evaluating interface designs for potential manipulation
  • Prioritizing which patterns to address (H2/H3 most severe)
  • Communicating harm to non-technical stakeholders
  • Regulatory compliance assessment

Limitations

The framework identifies harm categories but doesn’t quantify severity within categories. Multiple harms often co-occur (72% of dark patterns in the comprehensive taxonomy trigger multiple harm types. The psychological impact dimension (H4) is particularly difficult to measure.

Related: 01-atom—dark-pattern-definition