Don't Get Lost in the GAMP 5 Categories Maze | Valkit.ai
Don't Get Lost in the GAMP 5 Categories Maze
Master GAMP 5 categories: Navigate Category 1-5 risks, validation strategies, and best practices for GxP compliance and data integrity.
Steve Ferrell·
What Are the GAMP 5 Categories? (Quick Answer)
GAMP 5 categories are a classification system that groups computerized software used in regulated industries — like pharma, biotech, and medical devices — into four active categories based on complexity and risk.
Note: Category 2 (firmware) was removed from GAMP 5. Firmware is now classified as Category 3, 4, or 5 depending on its complexity.
If you work in a GxP-regulated environment, getting these categories wrong costs you — either through over-validating simple systems or under-validating complex ones. Both outcomes are expensive, and regulators notice both.
GAMP 5, published by the International Society for Pharmaceutical Engineering (ISPE), gives validation teams a risk-based framework to match validation effort to actual system complexity. The goal is simple: focus your resources where patient safety, product quality, and data integrity are genuinely at risk — and scale back where they aren't.
But in practice, many validation managers find the category boundaries blurry, especially when dealing with modern systems that mix off-the-shelf components with custom configurations, or when cloud and AI tools don't fit neatly into any single bucket.
That's exactly what this guide untangles.
I'm Stephen Ferrell, Chief Product Officer at Valkit.ai and a contributing author to the ISPE GAMP 5 Second Edition, with over two decades of hands-on experience guiding organizations through computerized system validation and GAMP 5 categories classification. As Chair of GAMP Americas and a member of the ISPE GAMP Global Steering Committee, I've seen where teams get stuck — and how to move faster without cutting corners.
Understanding the Core GAMP 5 Categories for Software
Steve Ferrell
Chief Product Officer
When we talk about GAMP 5 categories, we are essentially trying to answer one question: "How much can we trust this software out of the box?"
The GAMP® 5: A Risk-Based Approach to Compliant GxP Computerized Systems Guide isn't a rigid set of rules, but a framework. It assumes that as software becomes more unique to your specific business process, the risk of "bugs" or logic errors increases. Therefore, your validation rigor must increase alongside it.
In our experience at Valkit.ai, we see many teams treating these categories as rigid "buckets." However, the Second Edition of GAMP 5 (released in 2022) encourages us to view them as a continuum. A system might be 90% Category 4 but have a small Category 5 custom script.
Why Category 2 was Removed from GAMP 5 Categories
If you’ve been in the industry long enough, you remember GAMP 4. Back then, Category 2 was reserved for "Firmware." This usually meant the hard-coded logic inside a piece of hardware, like a simple temperature controller or a PLC (Programmable Logic Controller).
So, why did it vanish? Technology evolved. Modern firmware is no longer "simple." It often includes complex operating systems and configurable parameters. To keep things accurate, GAMP 5 absorbed firmware into the other categories.
A simple, non-configurable firmware chip is now Category 3.
A PLC that you configure with specific logic is now Category 4.
A custom-coded controller built in-house is Category 5.
This shift was a major milestone in the GAMP® 5 Second Edition, reflecting 14 years of technological progress.
How GAMP 5 Categories Determine Validation Effort
The category you choose is the primary driver of your validation strategy. It dictates the "V-model" approach—the lifecycle of planning, specifying, and testing.
According to scientific research on risk management options, applying a risk-based reduction can lower validation effort by 30–50% without compromising quality. This is achieved by focusing on "fit-for-use" testing.
Category 1: We check that it’s installed and the version is correct (IQ/OQ). We don't test the source code of Microsoft Windows.
Category 5: We perform a full Software Development Life Cycle (SDLC), including code reviews and design qualifications, because no one else has tested this code before.
Deep Dive into Software Categories 1 through 5
Let’s get into the weeds of each category. Understanding these nuances is the difference between a smooth audit and a "483" observation from the FDA.
Category 1: Infrastructure and Layered Software
These are the "utilities" of the digital world. They aren't designed for GxP tasks specifically, but they provide the environment where GxP tasks happen.
Examples: Windows, Linux, Oracle Database, SQL Server, and even office suites like Excel (when used for simple data entry).
Validation Approach: We focus on the installation and the environment. Does the database have enough storage? Is the OS patched? We leverage the fact that these are used by millions of people—the vendor’s own quality processes are robust enough that we don't need to re-verify the core functionality.
Category 3: Non-Configurable Software Examples
Category 3 covers Commercial Off-The-Shelf (COTS) software that you use "as-is." You might enter some basic settings (like your company name or the date), but you aren't changing how the software processes data.
Examples: A standalone software for a laboratory scale, a simple pH meter interface, or a data logger that comes with fixed reporting tools.
Validation Approach: You need a User Requirements Specification (URS) to justify why you bought it. Validation usually involves an Installation Qualification (IQ) and an Operational Qualification (OQ) to prove it performs as the vendor promised in your specific environment.
Category 4: Configurable Software and Complex Systems
This is the most common category for major enterprise systems. You aren't writing new code, but you are "configuring" the system to follow your business rules. This might involve setting up workflows, defining user roles, or creating custom report templates.
Examples: LIMS (Laboratory Information Management Systems), ERP (Enterprise Resource Planning), MES (Manufacturing Execution Systems), and SCADA.
Validation Approach: This is where the work gets heavy. You must validate the configuration. If you tell the LIMS to "reject any sample over 40 degrees," you must prove it actually does that. This requires Functional Specifications (FS) and a thorough risk assessment of your specific settings.
Category 5: Custom and Bespoke Software Risks
This is the "Wild West" of validation. Category 5 is software written specifically for you, either by your in-house IT team or a third-party developer.
Examples: A custom-built interface between two incompatible systems, a complex Excel spreadsheet full of VBA macros, or a bespoke application for a novel manufacturing process.
Validation Approach: This requires the most rigorous validation. Because the code is unique, the risk of "unknown unknowns" is high. You need a full SDLC, design qualification, code reviews, and extensive User Acceptance Testing (UAT).
Integrating Hardware Types and Modern Technology
While software categories get all the attention, GAMP 5 also categorizes hardware. This is crucial for systems that are "tangled" together, like a robotic arm controlled by a custom script.
Hardware Type 1 (Standard): Off-the-shelf servers, workstations, and network switches. You just document the model and version.
Hardware Type 2 (Custom): Custom-built circuit boards or sensors. These require detailed design documentation and rigorous acceptance testing.
Cloud/SaaS: Most SaaS platforms fall into Category 4. Even though you don't own the server, you are configuring the software. The challenge here is "leveraging the supplier." You shouldn't redo testing the vendor has already done.
AI/ML: AI is tricky because it "learns." GAMP 5 now provides specific guidance (Appendix D11) on handling the risks of non-linear software. The focus shifts toward data integrity and ensuring the "model" remains within validated boundaries.
Best Practices for Risk-Based Classification
Assigning GAMP 5 categories shouldn't be a solo mission. It requires a multidisciplinary team—IT, Quality, and the "Process Owner" who actually uses the system.
The "Deadly Sins" of GAMP Implementation
In our work at Valkit.ai, we’ve seen the same mistakes repeated for decades. Here are the pitfalls to avoid:
The "Everything is Cat 5" Fallacy: Thinking that because a system is important, it must be Category 5. This leads to massive over-validation and wasted money.
Ignoring the Supplier: If your LIMS vendor has a 500-page validation package, use it. Don't start from scratch.
The Spreadsheet Trap: Treating a complex Excel sheet with 50 macros as "Infrastructure" (Cat 1). If it has logic, it’s likely Cat 5.
Skipping Risk Assessment: Categorizing a system without looking at the ICH Q9 principles. The risk isn't just in the software; it's in the process the software supports.
Embracing Computer Software Assurance (CSA)
In 2025, the FDA finalized its Computer Software Assurance (CSA) guidance. This aligns perfectly with GAMP 5. CSA encourages "unscripted testing" for low-risk features and "scripted testing" only for high-risk, GxP-critical functions. This is the ultimate "fit-for-use" strategy.
Frequently Asked Questions about GAMP 5 Categories
What is the difference between Category 3 and Category 4?
The line is "configurability." If you use the software exactly as the vendor installed it, it's Category 3. If you have to go into the settings to create specific workflows, user groups, or business rules that change how the system behaves for your company, it's Category 4.
How does the GAMP 5 2nd Edition handle AI and Cloud?
It treats them with a "leveraged" approach. For Cloud/SaaS, you rely heavily on the supplier's SOC2 reports and their own internal validation. For AI, it introduces a lifecycle that accounts for model training and data bias, focusing on the integrity of the data used to "teach" the system.
Can a single system contain multiple GAMP categories?
Absolutely. A common example is a manufacturing line. The Operating System is Category 1, the PLC firmware is Category 3, the SCADA system is Category 4, and the custom reporting scripts are Category 5. You should validate the system based on the highest category involved, while scaling the testing for the lower-category parts.
Conclusion: Stop Drowning in Paperwork
Validation shouldn't be a "monumental task with a thousand moving parts." When you correctly apply GAMP 5 categories, you stop guessing and start measuring.
At Valkit.ai, we built our platform to automate exactly these complexities. By using AI-powered digital validation, we help organizations in Indiana, Scotland, and beyond move from "Paper-on-Glass" to true digital execution.
Whether you are dealing with a simple Category 3 lab tool or a massive Category 4 ERP rollout, our platform reduces validation costs by up to 80% and slashes timelines from weeks to hours. We do this through smart automations, "cloning" of validated states, and built-in compliance tools that ensure you are always audit-ready.
Don't let the "maze" of categories slow down your innovation. Focus on the science; let us handle the validation.
