The AI Training Data Guide

Everything engineering teams need to source, label, validate, and scale the datasets that train modern AI.

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13 guides

Fundamentals 9 min

How much training data do you need to train a model?

How much training data you need depends on your task, model type, and data quality.

Fundamentals 8 min

Synthetic data for AI: how synthetic training data works

Learn what synthetic training data is, how it's generated from scratch or from existing data, and when it can replace real data for training AI models.

Fundamentals 11 min

Training data quality: labels, coverage, and bias

What makes a training dataset good — and how to measure and improve label quality, coverage, and bias for better model performance.

Fundamentals 10 min

What is AI training data?

Learn what AI training data is, the types models need, and how teams source it — from real-world data or synthetic generation.

Methods 7 min

Generate vs. annotate: building labeled datasets

Compare generating training data with built-in labels vs.

Methods 12 min

How to build a dataset for LLM fine-tuning

How to assemble or generate a high-quality LLM fine-tuning dataset: sourcing, format, labels, quality, and how much data you actually need.

Methods 8 min

Preparing unstructured data for AI training: documents, transcripts, and notes

How to turn messy or sensitive documents, transcripts, and notes into safe, training-ready data using extraction and NER de-identification.

Comparisons 12 min

Synthetic data vs. prompting an LLM to generate training data

Purpose-built synthetic data generation vs.

Data Collection 10 min

Domain-specific training data for specialized models

Why general-purpose data underperforms on specialized tasks, and how to build a domain-specific training dataset that makes narrow models reliable.

Compliance 10 min

AI training data for regulated industries: HIPAA, PII, and privacy

How healthcare and finance teams build compliant AI training data: de-identify real PHI and PII, or generate synthetic data with none.

Agents and RL 8 min

Reinforcement learning environments and the modern RL stack

Learn what reinforcement learning environments are and how teams build, scale, and evaluate them with the modern RL stack.

Agents and RL 9 min

How to build RL evaluation datasets and benchmarks

Learn how to build RL evaluation datasets with verifiable ground truth, controllable difficulty, and no contamination risk.

Agents and RL 9 min

Building test data and environments for AI agents

How to build ground-truth-labeled test data and simulated environments for training and evaluating AI agents at scale.