LLM Fine-Tuning Methods: Best Practices for Success

َApril 12th, 2025

Hands typing on a laptop keyboard, with the screen displaying lines of code, data graphs, and visualizations, all set against a futuristic background with glowing blue and purple data streams and network patterns, illustrating LLM fine-tuning.

What is Fine-Tuning in LLMs?

Pre-trained language models have become a cornerstone of natural language processing (NLP), providing a robust foundation for various applications. To unlock their full potential, these models often require fine-tuning to adapt to specific tasks or domains. Fine-tuning involves refining the model’s parameters to suit the unique requirements of a particular task, such as sentiment analysis, chatbots, or summarization.

Diagram comparing LLM pre-training with fine-tuning (SFT or RLHF), showing the progression from a random model to a fine-tuned model using pre-training data and then in-domain data, with a branch for in-context learning.

Fine-tuning enables us to build upon the knowledge a model has already acquired, making the process more efficient and cost-effective. By fine-tuning a pre-trained model, we can enhance its accuracy, adaptability, and contextual relevance in our applications, ultimately driving better outcomes and user experiences.

Diagram comparing LLM pre-training (computationally demanding, large unlabeled dataset) with fine-tuning (computationally inexpensive, small labeled dataset).

Why is Fine-Tuning Essential in 2025?

In 2025, fine-tuning is not just an option but a necessity for organizations seeking to leverage LLMs effectively. While general-purpose LLMs offer broad capabilities, they often fall short when it comes to the specificity and accuracy required for specialized applications. For instance, in highly regulated industries like healthcare, finance, and law, fine-tuning ensures that LLMs understand and accurately apply industry-specific terminology, regulations, and workflows.

 
Infographic showcasing top AI use cases across various industries, including customer experience, supply chain, predictive analytics, and fraud detection, where fine-tuned LLMs can be applied.

Upload Your Dataset:

Consider a real-world example: Johnson & Johnson is using LLMs fine-tuned on medical literature to accelerate drug discovery. For example, an industrial-safety solutions company implemented an AI-powered tool using a fine-tuned Cohere Command R+ LLM to process customer inquiries and generate accurate responses, immediately improving its customer support operations. Similarly, companies are fine-tuning chatbots to answer support tickets with empathy and accuracy, which reduces agent workload.

With the rise of smaller, more efficient models, fine-tuning offers a cost-effective way to achieve superior performance in niche applications.

Methods for Fine-Tuning LLMs

In this section, we will explore three primary methods for fine-tuning LLMs: supervised fine-tuning, reinforcement learning from human feedback (RLHF), and parameter-efficient fine-tuning (PEFT).

Supervised Fine-Tuning

Diagram illustrating supervised fine-tuning of a Pretrained Language Model (PLM) using an annotated task-specific dataset, leading to task-adapted models for summarization, classification, and generation.

Supervised fine-tuning involves using labeled data to fine-tune a pre-trained model. This method is useful when the goal is to create a model that can perform a specific task or handle a specific domain.

This method is particularly useful in applications such as sentiment analysis, text classification, and named entity recognition.

Some key techniques used in supervised fine-tuning include:

Hyperparameter tuning:

Hyperparameter tuning involves adjusting the hyperparameters of the model, such as learning rate, batch size, and number of epochs, to optimize its performance. This is typically done using techniques like grid search, random search, or Bayesian optimization. By adjusting these hyperparameters, the model’s performance on a specific task can be improved.

Transfer learning:

Transfer learning involves using a pre-trained model as a starting point for fine-tuning. The pre-trained model has already learned general patterns and representations from a large dataset, and fine-tuning involves updating the model’s weights to specialize it for a specific task. This approach can be particularly effective when the target task is similar to the task the pre-trained model was trained on.

Multi-task learning:

Multi-task learning involves training a model on multiple tasks simultaneously. The model learns to share knowledge and representations across tasks, which can improve its performance on each individual task. This approach can be particularly effective when the tasks have similar input and output spaces.

 

Few-shot learning:

Few-shot learning involves training a model on a small amount of data, typically 1-5 examples per class. The model learns to generalize from this small dataset and is often able to perform well on unseen data. This approach can be particularly effective when the target task has similar patterns or structures to the few-shot data.

Reinforcement Learning from Human Feedback (RLHF)

Diagram illustrating the Reinforcement Learning from Human Feedback (RLHF) process for LLM fine-tuning, showing interaction between RL algorithm, environment, and reward prediction model guided by human feedback.
Content from Creative Commons, licensed under CC BY-SA 4.0.

RLHF involves using human feedback to fine-tune a pre-trained model. This method is useful when the goal is to create a model that can perform a specific task or handle a specific domain, and human feedback is available.

RLHF is often used in applications where the primary goal is to create a model that can perform a specific task or handle a specific domain, and human feedback is available. This method is particularly useful in applications such as conversational AI, text summarization, and language translation.

Some key techniques used in RLHF include:

Reward modeling:

  • Reward modeling involves designing a reward function that encourages the model to perform the desired task.

Proximal policy optimization (PPO):

  • PPO involves using a variant of policy gradient methods to optimize the model’s policy.

Comparative ranking:

  • Comparative ranking involves ranking the model’s outputs based on human feedback.

Group Relative Policy Optimization (GRPO):

It is a reinforcement learning algorithm used to train large language models, improving on PPO by eliminating the need for a separate value function model, which reduces memory usage and computational requirements. GRPO achieves this efficiency by generating multiple outputs for each prompt and using the mean reward of these responses as a baseline. This approach has shown significant improvements in mathematical reasoning and problem-solving capabilities while using fewer computational resources.

Parameter-Efficient Fine-Tuning (PEFT)

PEFT involves fine-tuning a pre-trained model while reducing the number of parameters. This method is useful when the goal is to create a model that can perform a specific task or handle a specific domain, while reducing computational resources.

PEFT is often used in applications where the primary goal is to create a model that can perform a specific task or handle a specific domain, while reducing computational resources. This method is particularly useful in applications such as text classification, sentiment analysis, and named entity recognition.

Some key techniques used in PEFT include:

Weight pruning:

  • Weight pruning involves pruning the model’s weights to reduce the number of parameters.

Knowledge distillation:

  • Knowledge distillation involves training a smaller model to replicate the behavior of a larger model.

Quantization:

  • Quantization involves reducing the precision of the model’s weights and activations.

Step-by-Step Guide to Fine-Tuning LLMs

Fine-tuning LLMs involves several steps, including data preparation, choosing the right pre-trained model, configuring fine-tuning parameters, validation and evaluation, and model deployment.

Diagram of the iterative LLM fine-tuning lifecycle, showing stages: business understanding, data understanding, data preparation, modeling, evaluation, and deployment.

Data Preparation

Data preparation involves gathering a high-quality dataset relevant to the task or domain. This includes cleaning, tokenizing, and formatting the data.

Some key techniques used in data preparation include:

Data cleaning:

  • Data cleaning involves removing noise and inconsistencies from the data.

Data augmentation:

  • Data augmentation involves artificially increasing the size and diversity of the data.

Data preprocessing:

  • Data preprocessing involves transforming the data into a format that is suitable for the model.

Choosing the Right Pre-Trained Model

Choosing the right pre-trained model involves selecting a model that is suitable for the task or domain. This includes considering factors such as model size, architecture, and domain relevance.

Model selection:

  • Model selection involves selecting a pre-trained model that is suitable for the task or domain.

Model Evaluation

Model evaluation involves assessing the performance of the pre-trained model using various metrics, such as accuracy, precision, recall, F1-score, BLEU score, and ROUGE score. These metrics help determine how well the model has learned to perform the task or solve the problem. For instance, in the case of summarization, the BLEU score measures the similarity between the generated summary and the reference summary. By evaluating the model’s performance using these metrics, you can identify areas for improvement and refine the fine-tuning process accordingly.

Configuring Fine-Tuning Parameters

Configuring fine-tuning parameters involves adjusting hyperparameters such as learning rate, batch size, and number of epochs.

Some key techniques used in configuring fine-tuning parameters include:

  • Hyperparameter tuning: Hyperparameter tuning involves adjusting the hyperparameters of the model to optimize its performance.
  • Learning rate scheduling: Learning rate scheduling involves adjusting the learning rate during training to optimize the model’s performance.

Validation and Evaluation

Validation and evaluation involve evaluating the fine-tuned model on a hold-out validation dataset.

Some key metrics used in validation and evaluation include:

  • Batch normalization: Batch normalization involves normalizing the model’s outputs to improve its stability and accuracy.

Accuracy:

  •  Accuracy involves evaluating the model’s performance on a specific task or domain.

Precision:

  • Precision involves evaluating the model’s performance on a specific task or domain, while considering the class balance.

Recall:

  • Recall involves evaluating the model’s performance on a specific task or domain, while considering the class balance.

Loss:

  • Loss involves evaluating the model’s performance on a specific task or domain, while considering the class balance.

Model Deployment

Model deployment involves deploying the fine-tuned model in a real-world setting. Efficient deployment necessitates the use of specialized tools that cater to the unique demands of large language models (LLMs).

Some key considerations in model deployment include:

Scalability:

Scalability involves ensuring that the model can handle a large volume of data and traffic. Containerization technologies like Docker and orchestration platforms such as Kubernetes enable consistent and portable LLM deployment across various environments, facilitating rapid scaling and management.

Integration:

Integration involves integrating the model with other systems and tools. Frameworks like LangChain and LlamaIndex simplify the development of LLM-powered applications by offering tools for prompt engineering, API integrations, and streamlined function calling. OpenLLM allows the integration of various open-source LLMs with other services, enhancing the flexibility of AI application development.

Security:

Security involves ensuring that the model is secure and protected from unauthorized access. Guardrails AI is designed to enforce ethical compliance and safety standards, proactively updating its monitoring criteria based on the latest regulatory guidelines.

Different tools are available to facilitate efficient model deployment:

Cloud-Based Platforms:

Managed services like Google Cloud AI Platform, AWS SageMaker, and Microsoft Azure Machine Learning offer end-to-end services, simplifying infrastructure management, scaling, and maintenance. Google’s Vertex AI streamlines the process of building, training, and deploying machine learning models at scale, offering a unified API and integration with other Google Cloud services.

Open-Source Frameworks:

Open-source tools like Hugging Face Transformers, KServe, and MLflow provide flexibility and cost-effectiveness. Ollama simplifies LLM app deployment in production environments, supporting a wide range of inference engines and offering seamless API integration.

Inference Optimization:

Libraries such as vLLM are designed for fast LLM inference and serving, optimizing model performance. NVIDIA Triton Inference Server leverages GPUs to accelerate inference.

Workflow Automation:

Tools like Prefect, Metaflow, and Kubeflow automate and manage complex data workflows, enhancing the scalability and efficiency of machine learning operations.

Best Practices for LLM Fine-Tuning

Fine-tuning LLMs requires careful consideration of several best practices, including customization for domain-specific tasks, ensuring data compliance, and leveraging limited labeled data.

Ensuring data compliance involves handling sensitive or regulated data during fine-tuning.

Some key techniques used in ensuring data compliance include:

Data anonymization:

  • Data anonymization involves removing sensitive information from the data.

Data masking:

  • Data masking involves masking sensitive information from the data.

Data encryption:

  • Data encryption involves encrypting the data to protect it from unauthorized access.

Leveraging Limited Labeled Data

Leveraging limited labeled data involves efficiently fine-tuning with small datasets.

Some key techniques used in leveraging limited labeled data include:

Transfer learning:

  • Transfer learning involves using a pre-trained model as a starting point for fine-tuning.

Few-shot learning:

  • Few-shot learning involves training a model on a small amount of data.

Data augmentation:

  • Data augmentation involves artificially increasing the size and diversity of the data.

Fine-tuning your LLM with UbiAI

UbiAI homepage highlighting its capabilities to fine-tune, deploy, and evaluate custom Large Language Models (LLMs), presented as a full-stack LLM platform.

Fine-tuning your LLM with UbiAI is a streamlined process that simplifies the complex task of adapting your model to meet specific requirements.

UbiAI handles each step in the fine-tuning process as follows:

Upload Your Dataset:

UbiAI interface for choosing dataset type for LLM fine-tuning, with options like Text-Based, Document-Based, Image-Based, and Prompt and Response.

UbiAI supports a wide range of documents, including CSV files, text documents, spreadsheets, PDFs, and even scanned images, which are then used to fine-tune your LLM.

The platform allows for easy upload and processing of various dataset types, enabling you to leverage a diverse range of data sources.

Data Preparation and Curation:

UbiAI text annotation interface showcasing named entity recognition, with entities like 'CLAUSE_NUMBER' and 'LESSOR' labeled in a legal document for LLM fine-tuning data preparation.

With UbiAI, you can label and annotate your data: Curate your dataset with precision by labeling and annotating your data, ensuring it accurately reflects the task or problem you’re trying to solve.

Remove errors and inconsistencies:

Easily remove errors, inconsistencies, or inappropriate content from your dataset, guaranteeing that your model is trained on high-quality data.

Balance and preprocess your data:

UbiAI text generation interface using Llama-3 model, showing system and user prompts for sports story generation, the LLM's response, and options to rate or edit the response for fine-tuning.

Balance your dataset across different classes or categories, and preprocess your data to ensure it’s formatted correctly for the model, avoiding potential biases or imbalances.

Configure Hyperparameters:

UbiAI training configurations panel for LLM fine-tuning, displaying options to select model (SpaCy), set train/validation ratio, number of iterations, dropout, and batch size.

UbiAI allows you to configure hyperparameters, such as learning rate and batch size, to optimize the fine-tuning process.

Fine-Tune Your Model:

UbiAI platform interface showing the 'Train the model' dashboard for fine-tuning a PII dataset 2, with configurations for Named Entity Recognition using SpaCy.

UbiAI’s platform fine-tunes various Large Language Models (LLMs) to meet specific requirements, including Transformers, BERT, RoBERTa, LLMs such as Llama 3.1, Qwen 7B, Deepseek and more, using your dataset and hyperparameters, adapting the model to meet your specific needs.

Evaluate and Refine:

UbiAI Training Evaluation dashboard displaying graphs for BLEU score, ROUGE-1, ROUGE-2, and ROUGE-L metrics, indicating model performance improvement during LLM fine-tuning.

UbiAI provides a range of evaluation metrics to assess the performance of your fine-tuned model, including precision, recall, F1-score, accuracy, ROUGE and BLEU scores.

Conclusion

Fine-tuning LLMs is a crucial aspect of modern deep learning, particularly when dealing with large-scale models such as foundation models in generative AI. By following the best practices outlined in this guide, developers can create models that are tailored to specific tasks or domains, while reducing computational resources.

Fine-tuning LLMs has numerous applications across various industries, including sentiment analysis, chatbots and virtual assistants, summarization, and domain-specific applications. By leveraging the knowledge of pre-trained models, fine-tuning enables developers to create models that are accurate, adaptable, and contextual.

In the future, we can expect to see even more innovative techniques and applications of fine-tuning LLMs. As the field of NLP continues to evolve, fine-tuning will remain a crucial aspect of creating accurate, adaptable, and contextual models.

Key Takeaways

  • Fine-tuning LLMs is a crucial aspect of modern deep learning, particularly when dealing with large-scale models such as foundation models in generative AI.
  • Fine-tuning enables developers to create models that are tailored to specific tasks or domains, while reducing computational resources.
  • Fine-tuning has numerous applications across various industries, including sentiment analysis, chatbots and virtual assistants, summarization, and domain-specific applications.
 

Unlocking the Power of SLM Distillation for Higher Accuracy and Lower Cost​

How to make smaller models as intelligent as larger ones

Recording Date : March 7th, 2025

Unlock the True Potential of LLMs !

Harnessing AI Agents for Advanced Fraud Detection

How AI Agents Are Revolutionizing Fraud Detection

Recording Date : February 13th, 2025

Unlock the True Potential of LLMs !

Thank you for registering!

Check your email for the live demo details

see you on February 19th

While you’re here, discover how you can use UbiAI to fine-tune highly accurate and reliable AI models!

Thank you for registering!

Check your email for webinar details

see you on March 5th

While you’re here, discover how you can use UbiAI to fine-tune highly accurate and reliable AI models!

Fine Tuning LLMs on Your Own Dataset ​

Fine-Tuning Strategies and Practical Applications

Recording Date : January 15th, 2025

Unlock the True Potential of LLMs !