Blog
October 5, 2025
Synthetic Test Data vs. Test Data Masking: Why You Need Both
Data Management,
Security & Compliance,
DevOps
When it comes to test data strategy, many organizations survey their options and get caught between two approaches: synthetic test data vs. test data masking.
As agentic development continues, scaling enterprises are looking for a data approach that balances compliance with speed. Synthetic test data is seen as the faster choice for getting data when you need it, while test data masking will meet stringent compliance requirements. Some may feel inclined to pick and choose, but both approaches have a lot to offer.
In this blog, we’ll break down the use cases for synthetic test data vs. test data masking and help you make the right choice for your organization — which could be using synthetic data and masking together.
What is Synthetic Test Data?
Synthetic test data is a class of artificially generated data designed to reflect the structure, relationships, and behavior of real-world data. It can be referred to as “fake test data” or “simulated test data.”
Synthetically generated values are useful when:
No real data exists that matches schemas.
Compliance regulations restrict production data access.
You need a way to deliver deidentified, realistic data faster than existing masking techniques.
Unlike masked or anonymized data, synthetic test data is not a transformation of production data. It is entirely artificial, and unless there are capabilities available to fine-tune synthetic data generators, the data may not have the statistical and referential fidelity. Synthetic data with referential integrity isn’t the standard, but certain solutions (including Perforce Delphix Synthetic Data) can uphold it.
Because it can act as a substitute for sensitive data, synthetic data generation can mitigate security risk while greatly expanding test scenario coverage. For example, you can use it to test against broader sets of data that may not be available in your environment, such as edge cases, negative scenarios, new markets, and changes to business procedures.
Generating large volumes of synthetic test data is quick and easy, which can help accelerate development speed.
REPORT
Where Does Synthetic Data Usage Stand?
While 56% of enterprises surveyed in The Synthetic Data Market Gap report ranked synthetic data the most purpose-fit approach for protecting data in AI/ML workflows, 51% are not using synthetic data in AI/ML workflows. Find out more details about what is holding enterprises back and how you can get the most out of your synthetic data.
Types of Synthetic Test Data
The type of synthetic data you need depends on your test scenario. Here are the main types:
Sample Data
Sample data is the simplest form of synthetic data, created quickly by developers during testing. It ensures all fields are filled and is useful for specific tests (like credit card numbers). However, it’s unsuitable for large-scale testing due to a lack of accuracy and referential integrity which can increase bug risks and applications to fail due to mismatched data.
Rule-Based Data
Rule-based synthetic data is generated according to predefined business and technical rules. Unlike sample data, which may simply populate fields with plausible values, rule-based data intentionally satisfies validation requirements, geographic constraints, industry regulations, and application-specific logic. This enables teams to create highly structured datasets that reliably exercise specific test scenarios, edge cases, and business processes.
Say a healthcare provider is preparing to test patient registration, eligibility verification, and claims processing workflows. Rather than using real patient information, the organization can generate rule-based synthetic data resembling patient records. The dataset could include a representative demographic distribution consisting of 20% pediatric patients, 60% adults, and 20% seniors. Patient names can also reflect multiple languages and cultural backgrounds.
This is just one way that rule-based synthetic data can be used — maintaining utility while also securing privacy for regulations like HIPAA.
Anonymized Data
Anonymized data is synthetic replacement data rather than generated data. In data masking, synthetic or randomized values replace real, sensitive data to preserve security while keeping the essence of the real data (like fictious names). It’s ideal for reducing data privacy risk while leaving remaining data intact.
Agentic Data
Agentic data is production-like data that is enriched with the context, relationships, rules, and state required for autonomous AI agents to make decisions and execute real-world business processes safely and effectively.
Agentic data is data that enables an AI agent to reason, decide, and act — which is different from traditional test data that typically only requires raw records. It provides additional components for AI to act on, including operational, context, relationship, policy, state, and feedback data. This allows you to move at AI speed with confidence.
REPORT
How Do Your Peers Use Synthetic Data?
51% of organizations are using synthetic data in their portfolio approach for protecting data in non-production environment, according to our latest research. Explore surprising insights on synthetic data, AI, and the state of data compliance today in our report, compiled from a survey of 500+ enterprise leaders.
What is Test Data Masking?
Test data masking is the process of replacing sensitive data with deterministic, synthetic values that are realistic. Test data masking methods can include:
Data deidentification
Tokenization and re-identification
Masking is useful because it provides fictitious but realistic data with referential integrity intact, both in the tables being masked and in the values that have been masked. Proper masking techniques should be irreversible, providing an ‘empty purse’ approach, whereby if a breach occurs, attackers gain no actionable value. For example, some native masking solutions only use dynamic data masking — which is reversible — while Delphix uses irreversible static masking.
With masking, you can protect sensitive data, reduce breach risk in non-production environments, and comply with data privacy regulations and industry standards while keeping the data available for use. When you use it in combination with test data automation, masking can ensure you streamline your compliance and data operations.
Test Data Masking vs. Synthetic Test Data
The main difference between test data masking and synthetic test data is that masked data is a demographically accurate, yet synthetic replacement for a real value. Synthetic data, on the other hand, is entirely artificial, but it can be generated to closely reflect real-world relationships, patterns, and edge cases when configured correctly.
Here’s an at-a-glance comparison of the two:
Aspect | Synthetic Test Data | Test Data Masking |
Data Source | Generated from source metadata or defined by operators or AI (as with the AI-first Delphix synthetic algorithm feature). | Derived from real production data, while protecting sensitive data values with realistic, referentially accurate synthetic replacements. |
Risk of Exposure | No risk, as data contains no personal information. | No risk if masking is properly applied and governed across environments. |
Customization | Highly customizable and adaptable for edge cases, negative scenarios, and new feature development. | Limited to the structure of the original data. |
Use Cases | New feature development, tailored testing, stress testing, chaos testing, API testing. | Data privacy, regulatory compliance, realistic testing, analytics, production-like test environments. |
Delivery Speed | Fast generation of data sets, even for very large numbers of records, in minutes. | Time is based on the size of the data and can range from minutes and hours to days and weeks. |
Quality Assurance | When defined correctly, ensures no sensitive data in the test data. | Provides irreversible, fictitious, but realistic data, deterministically. |
Referential Integrity | Can be achieved through built-in product capabilities like generators, depending on the synthetic data tool(s). As of this writing, this is not a common capability and not typical of the average synthetic data solution. | Inherent — a key part of data masking’s appeal. |
Business & Process Fidelity | Can be achieved through an approach like rule-based synthetic data. | Inherent — masking substitutes realistic data while maintaining the data correlations and dependencies for end-to-end application testing. |
When to Use Test Data Masking and Synthetic Test Data
Comparing test data masking vs. synthetic test data, it’s easy to see where one might be a better fit over the other. Whether you need customized data on demand or to protect existing data, test data masking and synthetic test data each have their individual strong suits.
Let’s look at their best fit scenarios and use cases:
Use Test Data Masking to Shield Sensitive Data and Preserve Integrity
Imagine testing environments that can be kept up to date with production and mirror the richness and complexity of your production data — without ever exposing actual sensitive information. That's the power of test data masking.
Benefits of Test Data Masking
Why is test data masking important? Well, using real production data poses significant security risks. Using obfuscated/encrypted data can also result in nonsensical values that aren't indicative of real-world functionality or performance.
By masking production data for testing, you’ll create a safe and compliant copy where sensitive values are replaced with fictious (yet realistic) alternatives.
In contrast to synthetic data generation, masking one’s existing production data source(s) maintains the real-world statistical fidelity of your data, while providing the deidentification required for non-production environments.
Use Cases for Test Data Masking
The best use cases for masking are for:
- Data privacy: Protect customer data, financial information, and other confidential details are protected from unauthorized access.
- Compliance: Meet stringent industry regulations (like GDPR, HIPAA, and PCI DSS) without sacrificing testing accuracy.
- Realistic testing: Evaluate application performance, functionality, and error handling against datasets that closely resemble real-world usage patterns.
- Non-production network safety: Ensure that sensitive data is never present in non-production environments without sacrificing speed or realism.
- End-to-end testing: Preserve cross-system referential integrity with masked data, to ensure seamless multi-application testing.
- Integration testing: Use masked data to maintain consistent relationships across disparate datasets, validating complex multi-system workflows.
WEBINAR
How to Pair Masking & Synthetic Data for an Effective Data Protection Strategy
In a recent webinar, Delphix experts Ilker Taskaya and Hims Pawar explain the different data protection approaches, so that you can better manage sensitive data. Watch and learn how synthetic data fits into your overall data protection strategy.
Use Synthetic Test Data to Tailor Data for Precise Testing
While masked production data excels in replicating real-world scenarios, synthetic data generation supports use cases that it may not be able to fulfill. Here’s a look into the instances synthetic test data would work best.
Benefits of Synthetic Test Data
While masking protects existing data, synthetic data creates realistic data where there is none. Synthetic data starts without production data, but you can generate new records designed to mimic the shape, behavior, or statistical traits of real-world data.
By using synthetic data, you ensure developers get the data they need when they need it, enabling faster data delivery and development. You can even generate data for edge cases and negative scenarios that don't exist in production.
Like data masking, synthetic data generation can help prevent sensitive data sprawl. While masking transforms and protects data before it’s used in non-production environments, using synthetic data means that sensitive data doesn’t leave production in the first place.
With Delphix, you generate purpose-built, realistic data that has referential integrity within and across sources. Using natural language, you can tailor and fine-tune the data for a particular use case, including new functionality, edge cases, and negative scenarios. This helps teams improve testing quality and get the data they need on demand.
Use Cases for Synthetic Test Data
The best use cases for synthetic test data are when:
- Limited or sensitive production data: When production data is unavailable, incomplete, or too sensitive to use, use synthetic data to provide safe, realistic datasets for development, testing, and innovation.
- Purpose-built test scenarios: Generate precisely targeted datasets to validate boundary conditions, rare events, negative scenarios, and other difficult-to-test business requirements.
- Chaos and resiliency testing: Create both realistic and intentionally anomalous data to uncover software defects, validate resiliency, and strengthen application reliability before release.
- API testing: Rapidly generate diverse input combinations and expected outcomes to validate API functionality, performance, and error handling at scale.
- End-to-end testing: Generate production-like datasets tailored to new workflows, features, integrations, and edge cases to improve end-to-end test coverage.
- Greenfield applications: Accelerate development of new applications by generating realistic, production-like data from day one, even when no historical production data exists.
- Right-sized test data: Create only the data you need, reducing storage, preparation time, and environment overhead while maintaining realistic test conditions.
- Data at agentic speed: Provision synthetic data in seconds or minutes instead of waiting hours or days for production-based masking and transformation processes to complete.
By generating synthetic test data, QA teams can achieve targeted testing, enabling focus on specific application aspects or functionalities with data tailored to the task at hand.
Testing no longer has to wait for a major release to be completed. It can be done at the feature level earlier in the development lifecycle, even before real data is available. This flexibility also extends to testing unusual or niche scenarios where QA teams can find potential issues that might be difficult to replicate with real data alone.
The Winning Formula: Test Data Masking and Synthetic Test Data Generation
What’s the secret to success for the world’s largest enterprises? A combined approach. Masked data and synthetic data generation, used together, will help you achieve the best results.
Masking production data for testing safeguards sensitive information for non-production environments in a repeatable, deterministic way. Meanwhile, synthetic test data generation fills gaps and allows targeted testing of specific scenarios.
Synthetic test data for software testing can complement masking, and vice versa. With Delphix, you can get both in a single platform.
The intelligent Delphix DevOps Data Platform unifies data masking, virtualization, and synthetic data, so that teams can validate, govern, and release software at AI speed. Using AI-first synthetic data generation and data masking, Delphix delivers realistic, governed test data on demand, helping teams accelerate development and testing while protecting sensitive data.
Get Demo
Get AI-Powered Synthetic Test Data and Masking with Perforce Delphix
Masking and synthetic data generation address different but complementary test data needs. Masking protects sensitive values while preserving the realism and relationships of production-derived data. Synthetic data fills gaps with purpose-built data for new functionality, specific testing scenarios, edge cases, and negative conditions.
With Delphix, you can use both capabilities within an intelligent test data automation platform. Delphix combines data delivery, automated masking, AI-first synthetic data generation, and central governance to help teams access realistic, protected test data on demand.
Related blog >> What is Delphix?
Ensure Compliance & Safeguard Against Data Breaches
Delphix centrally enforces masking policies aligned with GDPR, CCPA, HIPAA, and PCI DSS. Masked data that protects PII — as well as synthetic data that exposes no PII — removes the risk of real production data entering non-production environments.
Integrate Masking with Synthetic Data Generation
The Delphix DevOps Data Platform combines data masking, virtualization, and synthetic data generation to swiftly deliver secure, compliant data for development, testing, and analytics. Masking protects sensitive production data; synthetic data fills the gaps with realistic, scenario-specific data for new features, edge cases, and negative testing.
Together, they help accelerate releases, improve software quality, and strengthen governance. Delphix’s built-in AI remains in the customer environment, and customer data is not sent to the LLM.
Get to know the Delphix platform below:
Explore Data Masking & Synthetic Data Solutions
Experience how achieving compliance, simplifying data access, and supporting agentic development can be accomplished by pairing Delphix automated masking and AI-first synthetic data generation together. Request a demo to understand why top-tier enterprises rely on Delphix for managing, protecting, and provisioning data at AI speed.
SHARABLE PDF: Read More About Delphix & Its Benefits
This blog was originally written by Steve Karam but has been updated by Wayne R. Vincent.