Coding Standards: What Are They and Why Are They Important?

The goal of any software engineering team is to create high-quality software through a fast, efficient, and easily repeatable process. But when shrinking budgets, quickly approaching deadlines, and growing customer demands enter the equation, keeping your development process effective is easier said than done. 

The goal is always to produce high-quality code that’s easy to build on and maintain—another “easier said than done” objective. According to a recent report by CISQ, the estimated cost of poor software quality in the U.S. in 2022 was at least $2.41 trillion. 

To keep code clean and healthy, development teams must adhere to guidelines and best practices that enable them to create better code consistently. We refer to these coding rules, techniques, and accepted best practices as coding standards. 

Let’s take a closer look at coding standards to understand what they are, why they’re essential, and how to introduce them into your development process effectively. 

What Are Coding Standards?

Coding standards, also known as coding guidelines or programming style guides, are rules and conventions that developers follow when writing code. These rules define the code characteristics necessary to maintain a uniform codebase and facilitate collaboration among developers.

Teams implement coding standards to create and maintain clean, readable, secure, bug-free, and efficient code. Every development team should explicitly define its coding standards based on specific team and project characteristics, primarily the company’s industry and the programming language(s) their developers use. 

When coding standards are properly defined and implemented, your developers, even those who have just joined the team, can easily find their way around your code. In ideal circumstances, you want your source code to look like a single developer is writing, debugging, and maintaining it.  

Open vs. Closed Coding Standards

An “open coding standard" refers to coding guidelines that are accessible to the public, allowing for community collaboration and input. An example is “CERT”, a secure coding standard that takes the form of an open, publicly available web-based wiki. The standards are created through a collaborative effort from the software development and security communities.

In contrast, a "closed coding standard" refers to coding rules enforced within a company. These rules are not publicly shared, meaning only developers within that organization can access the detailed guidelines. 

An example of a closed coding standard could be a company's internal style guide that dictates precise naming conventions, commenting practices, and specific coding patterns unique to their system architecture, which they do not disclose to external developers.

The main difference between open and closed standards is how quickly they change. Open standards tend to be extremely dynamic. Guidelines change constantly and rapidly to reflect evolving best practices. Closed standards, however, evolve based on organizational workflows, priorities, and technologies.

Key Considerations When Choosing Between Open And Closed Coding Standards

Should you choose open coding standards or create custom guidelines for your organization? Here are some key factors to consider first:

Maintainability and Consistency: Because open coding standards are very dynamic, relying too much on them can render the codebase inconsistent over time, making it harder to maintain. With closed standards, however, guidelines change less frequently, and when changes are made, they are done in line with the organization’s goals and technologies. 

Collaboration: While closed standards can promote consistency throughout the organization’s projects, they can make it hard to quickly get new members up and running as they have to first get acquainted with the coding guidelines. On the other hand, open standards reduce the onboarding time for new team members or contributors.

Security: If you’re developing a safety-critical product, keeping your coding standards internal might be better, as it allows you to protect sensitive aspects of the system architecture or algorithms. For instance, a bank might have a closed coding standard for their core banking system, detailing specific encryption methods and data handling protocols that are not shared with external developers. 

Resource-intensive: Creating internal coding standards can take a lot of time and require expertise, which smaller companies may not have. With open standards, the companies are not responsible for creating and updating the standards. 

Though closed standards make it harder to onboard new developers, they promote internal consistency and security, making them ideal for enterprise apps or safety-critical products. On the other hand, open coding standards are best suited for open-source projects or products that aren’t safety-critical. 

What Are Coding Conventions?

Coding conventions are programming language-specific guidelines that offer recommendations for keeping your code clean. These recommendations focus mainly on programming style and organization best practices. They help maintain consistency but allow some flexibility. 

Different programming languages and communities may have their specific conventions, but here are some common coding conventions that are widely followed across various languages:

• Formatting: Be consistent in formatting throughout the codebase. Use an automated tool or formatter (black for Python, Prettier for JavaScript, etc.) to ensure consistent formatting throughout the codebase.

• Indentation: Use consistent indentation (usually 2 or 4 spaces) to improve readability.

• Naming Conventions: Use descriptive names for variables, functions, classes, etc. Follow a consistent naming convention (e.g., CamelCase, snake_case) depending on the language. Whatever naming convention you choose to use, stick to it.

• Braces and Parentheses: Use consistent placement of braces and parentheses.
  
  
• Comments: Write clear and concise comments for complex code sections. Avoid unnecessary comments that state the obvious. Be specific and concise. Write enough to provide the proper context, but don’t overexplain. Tools like Better Comments and Mintlify are great for helping you write good comments. 
  
  
• Whitespace: Use whitespace effectively to enhance code readability. Avoid excessive or unnecessary whitespace.
  
  
• Code Line Length: Limit the length of lines to improve readability. Many style guides recommend lines not to exceed 80 or 120 characters.
  
  
• Function/Method Length: Keep functions/methods short and focused on a specific task. Long functions should be broken down into smaller, more manageable ones.
  
  
• Error Handling: Implement proper error handling and communicate errors clearly. The goal is to identify and properly respond to errors and exceptions. When you have clear guidelines for reporting, logging, and handling errors, your code becomes more reliable and, over time, more error-proof. 
  
  
• File Organization: Organize code into logical sections or modules. Follow a consistent file and directory structure.

Once your team agrees upon what coding conventions are important to the organization and officially adopts them, they become an integral part of your coding standards—which is the fundamental difference between them. 

Coding conventions are recommendations, while coding standards are mandatory, non-negotiable rules your team has agreed to follow strictly.  

Why Coding Standards Are Important 

Coding standards help your team create high-quality code and software. But what does high-quality code mean?

High-quality code ensures that your software is safe, secure, and reliable for you and your users. When your code is these three things, you and your team can expect to reap the associated benefits.

They Make Upholding Code Quality Easier 

Coding standards set the rules and guidelines that enable your team to create more efficient code that’s easier to read, analyze, maintain, and extend. When code quality is high, every developer in your team, even ones who have just joined, should be able to easily understand any part of your code and work on it independently. 

Another benefit of following standards is reduced code complexity. Less complexity and better readability make code less vulnerable to errors. 

They Make Bug Fixing Easier 

Consistent and clean code makes it easier for developers to recognize code smells and anti-patterns and troubleshoot code when necessary. It is easier to catch errors and bugs early when your code is well-structured and clean, but it’s also easy to perform code reviews and test your code later in the process, before deployment or in production. 

Coding standards also make life easier for your testers, allowing them to focus on analyzing and reviewing your code’s logic instead of fixing formatting and style errors that can slip through the cracks when coding standards aren’t being followed.

They Help You Stay Compliant 

Compliance is a key consideration when creating coding standards. As software developers, regulatory compliance requirements must be met in almost every industry and region to avoid sanctions and fines. 

A recent report by Fenergo states that international financial regulators levied $189 million in fines for non-compliance with Anti-Money Laundering (AML) regulations, including Know Your Customer (KYC) and Customer Due Diligence (CDD) in just the first half of 2023.

Some of the most common regulations teams must take into consideration when defining coding standards include:

• The General Data Protection Regulation (GDPR) law, which is mandatory for all teams that handle the personal data of European Union (EU) citizens. One of the key principles is that software companies must request permission before using or deleting user data. 
  
  
• ISO 27001, jointly established by the International Standardization Organization (ISO) and the International Electromechanical Commission (IEC) to regulate information security management across international companies. It includes detailed regulations for creating, deploying, and managing your software to avoid data breaches and privacy issues. 
  
  
• The Payment Card Industry & Data Security Standard (PCI DSS) is a regulatory framework that must be followed by companies that deal with debit, credit, and other types of payment cards.
  
  
• The Health Insurance Portability and Accountability Act (HIPAA) requires companies that deal with healthcare data to protect these incredibly sensitive records, like medical histories and other health-related user details. 
  
  
• The National Institute of Standards and Technology (NIST) is a regulatory body for organizations from the U.S. and those who do business in the country. Companies must comply with their guidelines for preventing cyberattacks and data breaches. 

When your team knows which regulations it must comply with, adhering to coding standards helps ensure that software meets all necessary regulations, reducing the risk of non-compliance issues and associated financial penalties. 

They Help Keep Your Code Secure 

Many of the above-mentioned regulations provide guidelines for secure coding practices to be adopted by your DevSecOps team as part of your coding standards. 

According to a recent IBM survey, 51% of surveyed organizations planned to increase security investments in 2023, adding that the global average cost of dealing with a data breach in 2023 was $4.45 million. 

Security-related coding standards offer recommendations for implementing secure access control processes so that only authorized persons can access sensitive information and functionalities. 

They also guide your team in properly configuring libraries, frameworks, server environments, and more, to protect sensitive information and limit the chances of coding errors that can lead to vulnerabilities that can be exploited. 

Following coding standards can also help you uncover potential security issues, detecting things like secrets and insecure dependencies if they exist. They also ensure you aren’t using deprecated features or outdated protocols that can lead to breaches.

They Can Reduce Costs and Accelerate Time to Market 

Every organization strives to make its development process faster and more efficient over time to save money and increase revenue. According to a 2020 McKinsey report, companies with quicker and more efficient development cycles grow revenue four to five times faster than those that don’t invest in increasing development velocity and productivity.

By following coding standards, developers can increase speed and efficiency by avoiding common mistakes that can lead to errors and issues that slow down coding processes. According to our 2024 State of Software Quality report, 58% of developers say not having enough time is the single most common challenge faced during code reviews. Coding standards also help improve readability, making it easier and faster for dev teams to understand, change, and maintain their code. 

Better code quality also increases code reusability, another big time-saver. Highly functional code can also be scaled more efficiently, accelerating and improving collaboration among team members.

When code is clean and everyone follows the same standards, it becomes much easier for multiple team members to work on the same projects thanks to the consistency that standards introduce. Coding standards often emphasize maintaining robust documentation, making not just collaboration but onboarding new team members much easier and faster. 

Best Practices for Implementing Coding Standards 

The implementation of coding standards is a very subjective process and needs to be molded to the characteristics and needs of your team.

However, some generally accepted best practices can help you get on the right track and ensure you're getting the most out of the coding standards you’ve adopted.

Use Linters And Formatters

Linters (e.g., ESLint for JavaScript, Flake8 for Python) and formatters (e.g., Prettier, Black) check for stylistic issues and automatically adjust the formatting of your code to adhere to predefined style guidelines. This ensures consistency in areas like indentation, spacing, and line breaks.

To avoid the tedious task of running these tools anytime you make a change, integrate them directly into your development workflow (IDE, Git provider, etc.) and use pre-commit hooks to automatically check code before committing. Codacy supports the popular linters across all major languages, including JavaScript, Python, PHP, Go, and C#.

Automated Code Reviews

If your end goal is to ship your product to real users, you should use an automated code review tool. These tools expedite code reviews by analyzing your code for bugs, security vulnerabilities, and coding standard violations, providing a preliminary check on code quality before a human review. 

Use tools like GitHub Actions or Codacy to enforce standards automatically during code reviews. These tools integrate with major Git hosting services like GitHub and Bitbucket, allowing you to scan repositories, individual branches and pull requests. Some (e.g., Codacy) offer various security tools like SAST, IaC, secrets detection, and more.

Code Consistently

Let’s assume that, in a team of developers, programmer A uses a two-space indent and B uses his tab key. While this might be a non-issue in small projects, imagine these inconsistencies spread across hundreds of files and thousands of lines of code. 

That is why it’s important to have everyone working under a style: a collection of coding rules and guidelines that ensure consistent code formatting, code quality, compliance with language standards, and software security. Without one, shared resources may become mixed up as individuals struggle to remember the variable or file they are supposed to reference.

Promote Peer Code Reviews

Regular peer reviews allow developers to actively check each other's code against established guidelines, enabling them to identify issues on time and make the necessary adjustments.  

Encourage peer code reviews in your software team. One way to do this is using tools and software that streamline peer code reviews, such as GitHub, Bitbucket, and Codacy.

Another good practice is using pull request templates with checklists to ensure the new code meets all standards before it is merged into the main branch.

Install Version Control Policies

Your main branch is one of the most sacred parts of your business and should be protected at all costs. Enforce coding standards through branching and merge policies by setting rules that must be followed before code is merged into the main codebase. 

For example, a branching policy might require that developers create feature branches for specific tasks, ensuring that only completed, reviewed, and tested code is merged. 

Merge policies can then enforce checks, such as requiring a code review, passing automated tests, or confirming adherence to style guidelines before allowing the merge.

Be Aware of Industry Standards

Teams that develop video games and ones that work with healthcare providers have very different compliance, security, and safety requirements, making the coding standards they need to follow just as distinct. 

For example, MISRA C/C++ is a coding standard specifically written for the automotive and embedded industries, offering best practices for “the safe and secure application of embedded control systems and standalone software.”

Some other common industry-specific standards include:

• Aerospace industry standard DO-178C 
  
  
• Medical device standard IEC 62304 
  
  
• Telecommunications standard 3GPP TS 32.105
  
  
• Government and defense Common Weakness Enumeration (CWE), Defense Information Systems Agency (DISA), and Security Technical Implementation Guides (STIGs) standards

Research, recognize, and follow all relevant and established standards to meeting industry-specific coding requirements that ensure the development of secure, reliable, and compliant software.

Follow Language-Specific Standards 

Many coding standards and style guides already exist for most popular programming languages. Here’s a list of some readily-used ones: 

• Python: PEP8 (Python Enhancement Proposal) Style Guide for Python Code
  
  
• Java: Google Java Style Guide
  
  
• Javascript: Google JavaScript Style Guide
  
  
• C#: Microsoft C# Coding Conventions
  
  
• C/C++: SEI CERT for C/C++
  
  
• PHP: WordPress PHP Coding Standards
  
  
• R: Tidyverse R Style Guide
  
  
• Objective-C: Apple’s Cocoa Objective-C Coding Guideline
  
  
• TypeScript: Google TypeScript Style Guide
  
  
• Swift: Apple Swift Language Guidelines
  
  
• HTML/CSS: W3School HTML Style Guide and Coding Conventions

Be Able to Explain the Intent of Your Standards 

Before you begin implementing coding standards, be sure that your team understands why they are important. Your development team’s leadership should take time to summarize the intent of every coding standard so that the team understands the context of each rule. 

Also, briefly define how each rule is applied in the description. Educate your team on each coding standard you introduce by providing support materials to help them understand the advantages of following each coding standard.

To illustrate their importance more clearly, you can also offer your team real-life examples of what problems could arise from failing to follow coding standards.

Evaluate and Update Standards Regularly 

As your team and product evolve and evolve over time, evaluate your coding standards to determine whether they are still effective or need updating. If the proper due diligence was performed when picking and establishing your coding standards to start with, it’s unlikely that radical and constant changes will ever be necessary. 

Industry-specific standards like MISRA C/C++ are updated every few years, as well. Ensure your team is aware of these updates when they occur and adopts any new recommendations that have been introduced. 

5 Coding Standard Examples

Following good coding practices is key to maintaining a healthy codebase. Here are some best practices and conventions to follow when writing code.

1. Naming Conventions

Give clear and meaningful names to your variables, functions, and methods to help others and your future self quickly grasp the intent and behavior of your code.

Here’s an example of a poor naming convention:

The names “x” and “fn” do not describe anything about the code. The general rule is that if you have to read through the code to figure out what it does, you need to name your variables and functions better. Here’s a better version:

To maintain consistency throughout your codebase, choose a naming style and stick to it. For example, if you decide on camelCase, don’t switch to snake_case in the future.

2. Formatting and Indentation

Consistent indentation, line breaks, and formatting all play a key role in making code more readable and understandable. Below is an example comparing a good practice to a bad one.

The bad:

This code is all over the place. It wouldn’t even run because Python uses indentation to define code blocks.

This looks much better, and would run without issues:

Install a code formatter (like Prettier for JavaScript or Black for Python) directly in your IDE to automatically format your code. In addition, set up pre-commit hooks to ensure any new code is formatted before it gets committed.

3. Comments And Documentation

Comments clarify the code’s purpose and provide context for complex logic. Use them judiciously to describe why something is done, not just what is done.

This is bad practice:

The comment “# Add numbers” is overly simplistic and unnecessary. It’s obvious from the code itself that the function is adding two numbers, so this comment doesn't add value.

This is better:

The comment here is a well-written docstring (triple-quoted string), which is the preferred way to document a function in Python. It clearly explains the purpose of the function, what parameters are expected (a and b), and what the function returns (int), providing valuable context for anyone reading the code.

4. Error Handling

Handle errors gracefully and provide meaningful error messages to improve debugging and user experience.

This is bad practice:

If fetchData() were to fail, the code would simply log an “Error” text. However, we also need to know what caused the error to enable us to resolve the problem. 

This is better:  

This will show the message attached to the error object, allowing us to know the exact cause of the error.

5. DRY Principle (Do Not Repeat Yourself)

The DRY (Don't Repeat Yourself) principle is all about avoiding redundancy in code, so that changes only need to be made in one place, and the code is easier to maintain and less error-prone. 

If you notice that you're repeating the same code in multiple places, it simply means you're violating the DRY (Don’t Repeat Yourself) principle. That’s a sign to refactor your code and find a more efficient, reusable solution that doesn’t involve duplicating your code.

The block of code below violates the DRY principle:

In this code, the same operation (* 0.1) is repeated for both price1 and price2 to calculate tax1 and tax2. If you ever need to change the tax rate (e.g., to 0.12), you would have to update it in two places.

This follows the DRY principle:

Here the logic for calculating the tax is now encapsulated in a single function, calculate_tax. Instead of repeating price * 0.1 for each price, you simply call the calculate_tax function with the price as an argument. This makes the code cleaner, more reusable, and easier to maintain. 

If you need to change the tax rate, you only have to update it in one place (the function definition).

Uphold Coding Standards More Easily with Automated Tools

Embracing coding standards is a fundamental practice that elevates software development by enhancing consistency, readability, and security. Popular coding standards are widely accepted as best practices that have been proven to lead teams toward creating healthy, high-quality code more easily.  

However, maintaining coding standards across a project or team can be challenging without the right tools. Static code analysis tools are an excellent place to start. Tools like linters can help you automate the code review and analysis process, making it significantly easier for teams to adhere to established coding standards.

Codacy allows you to automate the static code analysis process by creating coding standards within the platform to ensure that groups of repositories follow the same security rules or coding conventions, for example. To see how it works, start your free 14-day Codacy trial today.