Opacus
Library for training PyTorch models with differential privacy.
- Status
- Generally available
- Last checked
- Aging · Sep 1, 2026
- License
- Open source
- Pricing
- Free tier · from $0
What it is
Opacus is a library that enables developers to train machine learning models using PyTorch while ensuring the privacy of individual data points through differential privacy techniques. This tool is essential for organizations and researchers who need to comply with strict privacy regulations or protect sensitive user information during model training.
Opacus stands out by providing a specialized library for integrating differential privacy directly into PyTorch training pipelines, ensuring compliance and privacy without sacrificing performance.
When it fits — and when it doesn’t
A good fit for
Teams that need to train PyTorch models on sensitive data while ensuring differential privacy compliance.
Researchers working on projects where individual data privacy is a critical concern.
Look elsewhere if
Projects requiring real-time model training and inference, as Opacus focuses on privacy-preserving batch training.
Teams that do not require or are not concerned with differential privacy in their machine learning models.
Known weaknesses
Each one links to the public issue, changelog or docs page it came from, where we have one.
- 01
Limited language support restricts non-Python users
Opacus is tightly integrated with PyTorch, which primarily supports Python
- 02
Complex setup for differential privacy parameters
Configuring noise multipliers and clipping norms requires deep understanding of differential privacy concepts
- 03
Performance overhead due to differential privacy techniques
Adding noise for privacy can significantly slow down training processes, especially with large datasets
- 04
Documentation lacks examples for advanced use cases
The official documentation focuses on basic integration and does not cover complex scenarios or optimizations in depth
What it does well
Supports differential privacy for PyTorch models
Easy integration with existing PyTorch training pipelines
High performance through optimized algorithms
Pricing
- Free tier
- YesOpen source — free to use
- Paid from
- $0
- Model
- Flat rate
- Enterprise plan
- No
Pricing not independently confirmed — check the vendor’s page.
Performance benchmarks
How Fast Is It?
Set up Opacus
Setup steps, common gotchas and what to check after 30 days.