DLLs vs. Static Libraries: Which is Better?

Developers often face a dilemma while choosing the right kind of library for their project – namely, whether to use a dynamic link library (DLL) or a static library. Both these libraries have different advantages and disadvantages, which can make it difficult for developers to decide which one is better suited to their needs. In this article, we will explore the pros and cons of both DLLs and static libraries and help you decide which one to use in your project.

Dynamic-link libraries (DLLs) and static libraries are two different ways of sharing code between different programs. In the case of DLL, the code is loaded into memory at runtime when a program needs to access it. In contrast, static libraries are linked with a program at compile-time. Both have their own advantages and disadvantages, which can make it difficult to determine which one is better. In this article, we’ll discuss the pros and cons of each method and help you decide which one is right for your project.


Dynamic-link libraries, also known as DLLs, are libraries that are loaded at runtime by a program when they are needed. The main advantage of this method is that it can save space because you only need one copy of the code on your system, which can be used by multiple programs. This is because the code is shared, and each program that uses the DLL will load it into memory as needed.

One of the main drawbacks of DLLs is that they can lead to dependency problems, especially when you’re using third-party libraries, as you may not have control over the libraries’ versions. This can cause issues if two or more programs are using different versions of the same DLLs, which can cause compatibility issues. DLLs are also prone to security vulnerabilities, and it can be harder to troubleshoot issues when they arise.

Static Libraries:

Static libraries are compiled and linked with the program at compile-time, meaning the code is included within the program itself. This means that the program contains the code it needs to function fully, making it less prone to compatibility issues. Because the code is linked with the program at compile-time, it’s also easier to deploy the program to different systems.

Static libraries can also be quicker and easier to develop because you don’t need to worry about version compatibility issues. It’s also easier to troubleshoot issues because everything is in the same place. On the downside, static libraries can take up a lot of space because every program that uses the library needs to have the code included.

Pros and Cons of Each:

When it comes to DLLs vs. Static Libraries, there are pros and cons to each method. DLLs are great for saving space because they can be shared across multiple programs. However, they can cause compatibility issues, and they’re more prone to security vulnerabilities. Static libraries, on the other hand, are less prone to compatibility issues and are easier to troubleshoot. However, they can be larger because every program that uses the library needs to have the code included.

When to Use Each Method:

So, when should you use DLLs and static libraries? Well, it ultimately depends on your project and your specific needs. If you’re concerned about space and want to share code across multiple programs with similar functionality, DLLs may be the right choice for you. If you’re concerned about compatibility issues or have a more complex project, static libraries may be the better option.

Static libraries are archives of compiled code that can be linked into an application at build-time. They are compiled into the final executable and become an integral part of the software. Using static libraries has several advantages. Firstly, they can be used offline and do not require any runtime dependencies, as they are directly linked to the application. This leads to faster application startup times, and the executable will work in any environment without the need for any additional libraries. Another advantage of static libraries is that they are easier to distribute. A developer can simply include the static library file along with their source code, and the user can simply compile it to create the executable. However, one major disadvantage of static libraries is their size – they can increase the size of an executable significantly, as all the compiled code is included in the executable.

On the other hand, dynamic link libraries (DLLs) are shared libraries that are loaded at runtime. They are compiled separately from the application and can be updated or modified without recompiling the entire program. This means that multiple applications can use the same DLL file, leading to reduced disk space usage and memory utilization. Additionally, since DLLs are loaded at runtime, they can be used to provide features like plug-ins and code modularity, enabling developers to create highly scalable software. However, DLLs come with their own set of disadvantages. One of the major issues with DLLs is that they come with runtime dependencies – if the required DLL is not installed on the user’s system, the application will not run. Moreover, loading DLLs at runtime can lead to slower application startup times.

The decision to use either DLLs or static libraries ultimately comes down to the specific requirements of the project. For instance, for small projects where the executable size is a constraint, it may be better to stick with static libraries. Similarly, if runtime dependencies are a concern, static libraries may be a better option. On the other hand, DLLs may be a better option for larger projects where scalability and modularity are key factors.

That being said, there are some situations where a combination of both DLLs and static libraries can provide the best of both worlds. For instance, using a DLL for frequently updated code and a static library for code that doesn’t change can help reduce the application’s size while providing modularity.

Another consideration for developers is the platform they are developing for. For Windows-based applications, DLLs are commonly used, while for POSIX-based systems like Linux, static libraries are typically used. However, there are exceptions to this rule and developers should weigh their options carefully before making a decision.

It is also important to note that the performance of both DLLs and static libraries can be impacted by how they are implemented. A poorly written DLL can lead to significant performance overhead, while an optimized static library can significantly enhance the performance of an application.


Choosing the right kind of library – DLLs or static libraries – is a crucial decision for developers. While static libraries have the advantage of being easier to distribute and faster to load, DLLs offer increased modularity and scalability. However, both have their own set of disadvantages and the right choice ultimately depends on the specific requirements of the project at hand. A good understanding of the pros and cons of both types of libraries can help developers make an informed decision on which one to use in their project. Additionally, developers should optimize the usage of both DLLs and static libraries by implementing them correctly to ensure efficient and fast-running software.

In conclusion, DLLs and Static Libraries both have advantages and disadvantages, and the choice between the two ultimately depends on each project’s specifications and needs. When choosing between the two, consider the size of the project, the amount of code required, and the potential for compatibility and security issues. By weighing the advantages and disadvantages of each method, you can make an informed decision on which one is the better choice for your situation.