711
Dictionary

DPO (Direct Preference Optimization)

A simpler alternative to RLHF that skips the reward model.

1 min readupdated 2026-07-04

/ quick answer

DPO fine-tunes directly on preference pairs (chosen vs rejected) with a contrastive loss. Cheaper and more stable than PPO; the default for open-source alignment. A simpler alternative to RLHF that skips the reward model.

A simpler alternative to RLHF that skips the reward model. DPO fine-tunes directly on preference pairs (chosen vs rejected) with a contrastive loss. Cheaper and more stable than PPO; the default for open-source alignment. In practice: Most fine-tunes of Llama-3 for chat use DPO on 10k-100k preference pairs.
Definition
DPO fine-tunes directly on preference pairs (chosen vs rejected) with a contrastive loss. Cheaper and more stable than PPO; the default for open-source alignment.
Example
Most fine-tunes of Llama-3 for chat use DPO on 10k-100k preference pairs.

/ frequently asked

What is DPO (Direct Preference Optimization)?

DPO fine-tunes directly on preference pairs (chosen vs rejected) with a contrastive loss. Cheaper and more stable than PPO; the default for open-source alignment.

What is an example of DPO (Direct Preference Optimization)?

Most fine-tunes of Llama-3 for chat use DPO on 10k-100k preference pairs.

Why does DPO (Direct Preference Optimization) matter?

A simpler alternative to RLHF that skips the reward model.

What should I learn after DPO (Direct Preference Optimization)?

Open the related workflows and prompts further down this page: they show how this idea is applied in a real task, step by step.

/ topics#ai#training

/ continue exploring

Related concepts

The vocabulary this page depends on.

  • →Fine-Tuning

    Continuing to train a base model on your own examples to specialize its behavior.

  • →RLHF

    Reinforcement learning from human feedback, the alignment technique behind ChatGPT.

  • →Model Distillation

    Training a small model to mimic a large one.

  • →LoRA

    Low-Rank Adaptation: cheap fine-tuning that patches only small matrices.

all dictionary →

Related workflows

Turn this into a repeatable process.

all workflows →

Related tool stacks

The tools that run it in production.

all tool stacks →

Comparisons & alternatives

Pick between the options.

all comparisons →