Software Development Time Estimation: Best Ways of Calculation
Estimating the amount of time your project needs is crucial to success and good management. Learn how to calculate a project timeline with various techniques.
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Have you ever been in a conversation where you are discussing a brilliant idea and all the details are clear and there is only a need to create software? You have a business idea that is easy to implement and you have the vendor you are going to outsource your project to. But here is the main question, how long will it take? Can you have it ready for next week? Next month? Year? This question is always a tough one to answer. So, how do you estimate the hours required for a software project in the right way?
Estimation is a complex matter and can’t be precisely defined. Usually, there are lots of changeable factors that impact the result. Incorrect estimation leads to lost revenue, enlarged budget, missed business opportunities, and so on.
So, we are here to discover how to estimate software development time.
The Importance of Software Development Time Estimation
First of all, let us share what we mean by software development life cycle time estimation. It’s the process of determining the amount of time required for a software engineer to complete a specific task. The estimation has to be applied also to each subtask. If you don’t want to lose time and additional money during the implementation phase, accurately calculated time of the project is the key. According to research conducted by Project Management Institute, 25% of projects fail due to inaccurate time estimation.
Underestimation of time can cause money loss. While the overestimation of the time and effort can lead to the fact that you will not get the project. Here are a few reasons why it is important to estimate programming time:
- Provides a guideline. It’s impossible to recognize a problem without first establishing all the expectations
- Helps manage uncertainty. It’s more convenient to know what can get done next week than it is to know what will get done next quarter
- Helps a team to be on the same page
- Helps adjust the roadmap
Estimating time for IT projects is beneficial to clients. Let’s see why:
- They can visualize the whole scope of work and plan the launch date
- There is transparency in the whole development process that positively impacts your business relationship
The main benefit for software development companies is that they know where to spend their time, what to prioritize, and how much.
We'll go through a few software development time estimation methods we use.
Guidance on How to Estimate Time for Software Development
The project timeline depends on the following factors:
- The team’s experience, seniority, and velocity
- The project’s complexity
- Risk factors
Usually, this process takes a couple of steps and we are here to share with you our software development time estimation template.
Try to understand the essence of the client’s idea. Discuss details like
- Technical documentation
- High-level requirements
- List of competitors/Analogous websites
- Personal preferences
Ask as many questions as you can: clarify the vision and discuss functional and non-functional requirements. All of these help with the most accurate estimate.
List the Details
Another useful software development time estimation example is to list all the details and activities you can remember regarding the future project and put them in the order in which they need to happen. Set a technical plan, the scope of work, and work out of scope. Then perform business analysis, and prepare to change your list with effort estimation. Also, don’t forget about non-technical tasks like:
- holidays/sick leaves
- administrative work
Elicitation of Requirements
At the next stage, we process information that is available and set up final data requests if needed. If the requirements are complete, we move forward to the next phase. But in case the obtained information is raw and lacks project specifics, we recommend initiating a product discovery service.
During this process, our business analysts perform an evaluation of the business, functional and non-functional requirements, and advise on the functionality. Search users’ pain points and get the best solutions to satisfy their needs. It is a cost-saving, risk-free input into your project development.
Software project time estimation also depends on the best tech stack for wanted functionality. Define your objectives to understand what you are going to deal with. For example, whether your project will be a web platform, a mobile application, or a cross-platform solution. Then, do research and discover what are the technologies used by your competitors in similar cases. Find out the reason they use this and what results they get in the end.
Example of what a technology stack may look like:
- API Application
- Web framework: Django/.NET Core...
- Programming language: Java/Python...
- Front-end Application
- Data Storage
- AWS S3...
Software Project Time Estimation Challenges
There may be lots of twists and turns that make the estimating process complicated. Usually, it’s difficult to answer how to better estimate software development time, as it changes every time the initial requirements change or other unexpected dilemmas appear. Other challenges that can impact software development estimates include:
- Engineers availability
- Different approaches to building software
- The productivity and experience level of the team
- Leaving quality assurance to the last day
- Unforeseen defects
- Issues with system/environment, software/library, design/architecture, etc.
- Non-engineering related questions
Software Development Time Estimation Methods
There are common software development time estimation techniques. Let’s take a closer look at them.
Method of Analogy
This method is mostly used when you have limited information about the project and it is based on the experience of work on previous projects. By using this method, the time and cost of developing similar projects are compared to a current one.
Poker Estimate Method
So, how do you estimate a software project in man-hours? We say try the approach brought by Agile project management. It works in a way that a team of engineers and business analysts (based on the client's request) do estimation separately. Then each team member declares how much time she or he needs to spend on a specific task. Questionable estimations are discussed together.
Work Breakdown Method
According to this approach, you divide the whole project into smaller manageable deliverables. This gives the opportunity to predict how much time a small task would take rather than calculate a project. Also, with this method, the client can see constant progress.
Tips From Inoxoft Expert
Before estimating time for software development, consider the following:
So, let's start with the most basic time estimation technique in software development that is the creation of the project strategic plan: objectives, milestones, deliverables, resources, and timeframes.
Break the Whole Project Into Smaller Milestones
Another useful step of estimating a timeline for a project is to break down the project into elements. This process brings clarity to what specific features need to be developed.
Project Size and Type
You can’t estimate the project soley on your previous experience of working on similar cases. The size, type, and scope of each project impact the estimation. The bigger the project is, the more integration it requires. The type of project matters as well, because developing mobile applications may need more time to complete than web platforms. All of this leads to the increased estimated time required to finish the project.
Don’t Forget to Leave a Buffer Time
Analyze your previous experience: how much of it is done, the estimated time for that project, and the actual amount of time it took to finish the project. Experts advise keeping a 15-20% time buffer to deal with any unexpected situations without lots of stress.
Analyze the Requirements Once Again
To create the functional breakdown of your solution in the most efficient way, you need to know the difference:
- Functional requirements based on the final perception of the future product. It is possible to visualize the final result by showing key business processes, sequence diagrams, and functional decomposition.
- Non-functional requirements define the system’s quality characteristics and attributes (installability, performance, interoperability, usability, scalability, security, etc.)
Get Different Perspectives on the Idea
Each perspective looks at the idea differently and this can provide a lot of interesting insights on the things that need to be done. The more viewpoints on the project you have, the easier it will be to choose the best approach.
Adopt Different Techniques
Our team uses a business analysis as one of the software development time estimation tools for product discovery. Some of them are:
- Prototyping for system capabilities and functional decomposition
- Interface analysis
- Feasibility analysis (whether the solution is practical)
- SWOT analysis
- Scope modeling and root cause analysis
- RACI matrix, roles and permissions matrix, and personas for roles evaluation
- User stories (how the functionality works to satisfy the user)
This was our time estimation for the software development template that varies depending on the project and its requirements. These approaches will be especially helpful for Agile teams.
Published at DZone with permission of Nazar Kvartalnyi. See the original article here.
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