← LLMs & Transformers
02 · LLMs & Transformers

What is Fine-tuning?

Fine-tuning is additional training that adapts a pre-trained model for a more specific behavior or task.

What is it?

Fine-tuning is additional training that adapts a pre-trained model for a more specific behavior or task.

It starts from an existing model and continues training on focused examples. Some methods update model parameters directly; others train adapters.

Think of it like...

Think of it like specialist training after general education. The learner builds on broad skills instead of starting from zero.

Specialist training after general education
Fine-tuning focuses a capable base model on a target behavior.

How it works

A base model is exposed to target examples. Training updates selected values, then evaluation checks the result.

1 · Base modelStart with broad skillsLoad a pre-trained model.
2 · Target examplesShow desired behaviorPrepare focused input and output examples.
3 · Additional trainingUpdate valuesTrain parameters or adapters on the examples.
4 · Specialized modelUse adapted behaviorThe model becomes more consistent for the target task.
5 · EvaluationCheck regressionsTest quality, safety, and general behavior.

Real-world examples

Support classification

Input: A customer ticket

System: Examples pair tickets with desired labels

Output: More consistent categories

Writing style

Input: A draft request

System: Examples demonstrate tone and format

Output: A more consistent draft

Structured output

Input: A document

System: Examples show the target schema

Output: More predictable fields

What it is NOT

Fine-tuning ≠ Pre-training

Fine-tuning: Targeted additional training

Pre-training: Broad initial training

Fine-tuning ≠ Prompting

Fine-tuning: Changes learned behavior through training

Prompting: Changes instructions at runtime

Fine-tuning ≠ RAG

Fine-tuning: Adapts model behavior

RAG: Retrieves external information at query time

Remember this

Fine-tuning is additional training that makes a pre-trained model more consistent for a specific behavior or task.

Independent video · Azure Neural voice

Video

visual explainer
specialist training · target examples · evaluationMP4 · H.264 + AAC
↑