AI glossary

What is fine-tuning?

Fine-tuning is further training of an existing AI model on a smaller, specific set of examples, so it gets better at a particular task, style or domain. It changes the model's weights, unlike prompting or RAG, which only change what you send it.

How does fine-tuning work?

You prepare many examples of inputs and ideal outputs and train the model on them for a short time. The model keeps its general knowledge but shifts towards your examples.

Why does fine-tuning matter?

Fine-tuning helps with consistent style or narrow tasks at scale. For most needs, better prompts or RAG are cheaper and easier to update.

An example

Example: A company fine-tunes a model on thousands of its past support replies so it answers in the company's voice by default.

Related terms

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Updated 18 October 2026 · Written by the Plintrix team