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Guide

Emily Watson6 min
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Most teams struggle to get enough good data for training and evaluation. Real-world data often contains personally identifiable information or protected health information, which creates legal and security risks. Synthetic data offers a way to generate realistic datasets without exposing real individuals or patients.

Why privacy matters for AI training data

When you train a model on real customer or patient records, you inherit every privacy risk attached to that data. A single breach can expose names, addresses, medical diagnoses, or other sensitive details. GDPR fines can reach 4 percent of global annual revenue, and HIPAA penalties in the U.S. can exceed $1.5 million per violation. Synthetic data lets you work with realistic patterns without storing or processing actual PII or PHI.

How synthetic data stays compliant

Synthetic datasets are generated from statistical models of real data. The output contains plausible values but never comes from actual individuals. Techniques include differential privacy, which adds statistical noise to prevent individual records from being recovered, and de-identification followed by re-synthesis. These methods reduce the risk of re-identification while preserving the statistical properties needed for training.

Real tradeoffs to consider

  • Synthetic data can miss rare or anomalous patterns that appear only in real datasets.
  • Models trained on synthetic data may need additional fine-tuning on a small set of real examples.
  • Generating high-fidelity synthetic text or interactions requires careful model selection and validation.
  • You must validate that synthetic distributions match real-world distributions across key features.

The key takeaway: synthetic data reduces privacy risk and legal exposure, but you must validate its realism and coverage for your use case.

How Coasty fits

Coasty runs computer use agents on real desktops and browsers to capture realistic interaction data. This approach yields high-fidelity synthetic datasets and trajectories for training and evaluating agents and models. Coasty’s synthetic data service is custom and contact-led, meaning you work directly with the team to design a dataset that matches your requirements.

Ready to explore how synthetic data can help you build privacy-safe AI? Book a data call with the Coasty data team to discuss your use case and see how a custom synthetic dataset could meet your needs: https://cal.com/coasty/coasty-data-call .

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