Best Practices

What are Gantt Charts: Advantages & Disadvantages (Example Included)

Jonathan Friedman
August 17, 2020
What are Gantt Charts: Advantages & Disadvantages (Example Included)

Gantt charts. You've likely used them before or heard of them while working on a project. Or maybe you're here because you recently joined a project, and a project team member just mentioned the term, but you're not quite sure what they are talking about. Whether you're an expert or a newbie, in this article, we'll share everything you need to know or want to know about Gantt charts, from their history and definition to best practices. We'll even go over Gantt chart advantages and disadvantages, and we'll detail how to create them through a real Gantt chart example.


While Gantt charts can be complicated, in the simplest of terms, they are project schedules. Nothing more, nothing less. Below is everything we will cover. Feel free to skip ahead.

  1. What are Gantt charts?
  2. Who uses Gantt charts?
  3. Why are Gantt charts used?
  4. What does a Gantt chart show?
  5. Gantt chart example
  6. Gantt chart software
  7. Advantages of Gantt charts
  8. Disadvantages of Gantt charts
  9. Gantt chart alternatives

Traditional Gantt chart

1. What are Gantt charts?

Gantt charts have been used since the early 1900s. While the first form of the chart was developed in the mid-1890s by Karol Adamiecki, a Polish engineer, it wasn’t until 15 years later that Henry Gantt devised his version. Henry Gantt enhanced Adamiecki’s work by showing interdependencies between bodies of work within a project. 

Gantt charts are a bar chart visualization of a project schedule. Each task and sub-task is listed vertically, with dates listed horizontally. They also list out and identify dependencies between tasks. 

Typically, use Gantt charts when there is a sequential order of events or easily identifiable hand-offs. An easy analogy to this is relay races. Runner two cannot start until runner one is complete. Similarly, runner three cannot begin until runner two is complete, and the sequence of events persists until all runners have run. 

Gantt charts are the ideal visualization for the project management approach, known as a waterfall methodology. That is group project tasks into linear sequential phases, where each stage is dependent on the previous. Then, every activity within the stage has an estimated duration of time it will take to complete. As every task is dependent on one another, you can forecast when the project will be complete. Additionally, when a task’s start date is delayed, or if a task won’t be completed until several weeks later, you can easily visualize the impact on the entire project’s completion. Gantt charts allow you to visualize the effect on the whole project because every task is connected with an estimated duration. As a result, Gantt charts are great for projects where the project length can be easily determined and where every phase and task depends on one another. 

2. Who uses Gantt charts?

Gantt charts are useful if you are a general manager or a project-based leader that plans and executes projects with a fixed duration. Below outlines a handful of users that benefit from the use of Gantt charts. However, Gantt charts are great for anyone looking to visualize work on a timeline.

Again, Gantt charts are great tools for anyone looking to build a project timeline where a project has a fixed duration. As a best practice, it is best to create and use a Gantt chart during the project planning phase and project execution phase, the second and third of five project management phases.

3. Why are Gantt charts used?

Gantt charts are excellent for organizations that need to visualize their programs and projects across time. They are especially useful for projects that have defined objectives that need to be completed by a specific date. Some examples of projects that use Gantt charts, or can benefit from using Gantt charts are below. Each of the below project types has a deadline as to when they need to be complete or have stage-gates. Stage gates are where each phase of the project have decision points, and the project cannot continue until that point is met. However, similar to the project end date, stage-gates usually have a deadline as to when they need to be complete.

Enterprise-wide strategic initiatives

Department-specific projects

Client delivery

4. What does a Gantt chart show?

While Gantt charts are not difficult to understand, they are tedious and time-consuming to set up and maintain. As a result, typically one person, or a team of individuals are responsible for managing project plans in the form of Gantt charts. However, we’ll get to that later. Nevertheless, Gantt charts always capture the same types of information.

Gantt chart types of data

Gantt chart dependencies, sometimes known as task links

One of the significant benefits of Gantt charts is the ability to identify and track dependencies. A dependency is when a task reliant on another task. We at TrueNxus allow you to identify and track dependencies. However, unlike other, more overly complicated project management software, we do not require users to define the type of task links, a specification as to how the tasks are connected. That is, are the tasks finish-to-start, start-to-start, finish-to-finish, and start-to-finish. Don’t worry if you don’t know what I’m referencing. Below are the definitions for the four types of task links that traditional Gantt chart software like Microsoft Project require.

Assume there are two tasks: Task A and Task B. Also, assume Task B is dependent on Task A.

Dependency definitions

You should know that such detail, which is great to have, is also the cause for so much of the learning curve in how to use Gantt charts. It also requires the project to know such connections before the work commences distinctly. Furthermore, our experience in managing hundreds of projects has shown us that maintaining such details results in no one other than the project manager supporting the plan, meaning there is no collaboration or accountability. Additionally, features such as this are counter-intuitive and the reason for the majority of projects to stand-clear of software that requires it (i.e., Microsoft Project, Smart Sheets, Wrike). As a result, we at TrueNxus developed a Timeline, a Gantt chart like view, without the clutter and annoyances of other software.

How to make a Gantt chart?

Now that you understand the attributes used in creating a Gantt chart, combine all of the knowledge to create your first project plan using a Gantt chart with the below steps.

1. Define the project timeframe

Use a Gantt chart in projects that have a start date and an end date. Think of the Gantt chart as a way to represent the project across time, which needs a beginning and an end.

2. Create logical groupings for tasks

While tasks are the basic building blocks for any project plan, it is typically an efficiency booster to create logical groupings for sets of tasks. While Gantt charts usually refer to groupings as phases, groups can be workstreams, work required for a deliverable, or any consistent way to categorize tasks.

3. Add tasks with start dates and due dates

Now, work backward. Start from when the project is scheduled to end and then build out the tasks you and your team need to execute to meet the objectives outlined to close a project. 

4. Assign task owners

Then, determine the people responsible for owning and executing the tasks. These individuals should be responsible for doing the work, but they should also be accountable to the entire project team for their successful delivery.

5. Break work up into sub-tasks

Sometimes a task is large enough that it makes more sense to break it down into smaller, more manageable activities. Breaking tasks down into sub-tasks also allows the project team to distribute work more effectively. For example, if a task requires multiple work efforts from numerous stakeholders, it’s better to break the task down into sub-tasks.

6. Identify dependencies

Document any dependencies between tasks. By identifying these connections in Gantt charts, you provide full visibility into both downstream and upstream impacts, resulting in real accountability. You can now hold team members accountable for their work by notifying them automatically when a dependent task due date or status changes.

7. Monitor and adjust work as plans change

Once the Gantt chart is complete, review the Gantt chart and adjust plans as necessary. Remember, a project plan is a living breathing document and inevitably plans change.

5. Gantt chart example

Now, let’s take a look at a Gantt chart example.

Situation

In this Gantt chart example, you are a consultant for Consultancy Alpha. Company Jupiter has hired you and your team to deliver a new strategy for increasing its global market share for widgets. In the engagement contract, Consultancy Alpha has agreed to provide the new strategic approach to Company Jupiter by December 31, 2020. 

Task

Given the situation, the engagement Partner has asked you and your team to put together a project plan to ensure that the final strategy recommendation can be delivered to Company Jupiter no later than December 31, 2020. 

Action

Understanding that the strategy recommendation needs to be delivered no later than December 31, 2020, you and your team decide to build a project plan in the form of a Gantt chart, and work backward. Creating the project plan, planning from end-to-start, you can plot everything that needs to happen, by whom, and by when.

Therefore, you and your team build out the below project plan, assign responsible stakeholders, and document start dates and due dates.

Project plan: Plan

 1. Plan

Project plan: Analyze

2. Analyze

Project plan: Design

3. Design

Project plan: Build

4. Build

Project plan: Test

5. Test

Project plan: Deliver

6. Deliver

Traditional Gantt chart

Result

As you can see in this Gantt chart example, by creating a project plan in the form of a Gantt chart, you and the entire project team have confidence in what it takes to deliver the strategy to Company Jupiter. Additionally, the Gantt chart becomes a living and breathing tool to ensure the entire project team stays on track. If things begin to steer off course, you can adjust the plan as needed.

6. Gantt chart software

Below is a list of a wide-variety of Gantt chart software providers broken out by online vs. offline.

Online Gantt chart software

As of August 2020; Prices quoted are annual billing for the product packages that include reporting and allows more than 15 users.

  1. TrueNxus (starting at $8.33 for first 5 users/month, then $7.50 for each additional user/month)
  2. Microsoft Project Online (starting at $30.00/user/month)
  3. Smartsheet (starting at $25.00/user/month)
  4. Wrike (starting at $24.80/user/month)
  5. ProjectManager (starting at $20.00/user/month)

Offline Gantt chart software

  1. Microsoft Project
  2. Microsoft Excel
  3. Google Sheets

Try our free Microsoft excel Gantt chart template.

7. Advantages of Gantt charts

Some of the advantages of using a Gantt chart include:

8. Disadvantages of Gantt charts

Some of the disadvantages of using a Gantt chart include:

9. Gantt chart alternatives

TrueNxus's timeline, a better alternative to traditional Gantt charts

While Gantt charts offer a lot of value, we at TrueNxus, and our clients, believe there is a better solution than traditional Gantt charts. That’s why we built the Timeline, a Gantt chart-like view of a project plan. The Timeline has all of the advantages of a Gantt chart, but without all of the disadvantages. It’s easy to set up and maintain, and it’s logical to the entire project team, not just project managers. TrueNxus’s Timeline feature is genuinely collaborative, meaning the whole project team will use it. 

TrueNxus’s Timeline enables change management

Unexpectedly, things happen, and tasks take longer than expected, or priorities shift. As these changes occur, you will be able to easily modify the project plan and reprioritize work in TrueNxus’s Timeline. Additionally, you’ll ensure transparency across all stakeholders. However, with traditional Gantt charts, this is not the case. As a result, you’ll take forever to update the project plan in a Gantt chart, and no one will look at it, resulting in frustration.

TrueNxus’s Timeline allows you to manage dependencies easily

If you are reliant on others, you can easily add dependencies in TrueNxus’s Timeline. By doing so, you will provide visibility into what everyone is on the hook for delivering. Additionally, as things change, you’ll be notified automatically, and you’ll be able to easily update the project plan, ensuring everyone is in sync.


Traditional Gantt charts allow you to define the type of task link, remember finish-to-start, start-to-start, etc. The ability to set task links is helpful in that you’ll get a new view of when the project will end. However, the resulting project end date isn’t real. You’ll still have to confirm every downstream impact with every stakeholder, reprioritize work, and hope that it works. Doing so is exhausting, and you’ll mainly be herding cats and chasing a moving target. Such a feature is overcomplicated and does not meet the intended benefits of Gantt charts. We at TrueNxus have lived this painful experience several times over. That’s why we built the Timeline so that you can intuitively visualize and manage task dependencies.

Plan and execute projects with ease

TrueNxus’s Timeline was built not only for professional project managers and project management offices (PMO), but also accidental project managers and the people executing the day-to-day work. The Timeline is intuitive and collaborative, allowing you and your team to plan and execute projects with ease.

If you’re thinking about using a Gantt chart to manage your projects, it’s time you had a simpler solution that you and your team will actually use. TrueNxus’s Timeline is the answer. Try TrueNxus today for free.