Product management glosary

Fibonacci Agile Estimation

What is Fibonacci Agile Estimation?

Fibonacci Agile Estimation is a technique used in Agile project management to estimate the effort required to complete tasks and user stories. It is based on the Fibonacci sequence, a mathematical series of numbers in which each number is the sum of the two preceding ones, starting from 0 and 1. The technique helps project teams to assign relative sizes to tasks, making it easier to prioritize and allocate resources effectively.

Why use Fibonacci Agile Estimation?

Estimating the effort required for tasks is a critical aspect of project management. Accurate estimation helps teams to allocate resources effectively, manage expectations, and deliver projects on time and within budget. Traditional estimation techniques often rely on time-based estimates, which can be prone to inaccuracies and subjectivity. Fibonacci Agile Estimation addresses these issues by providing a more objective and consistent approach to estimating effort.

Using the Fibonacci sequence in Agile Estimation has several benefits:

  • Relative sizing: The technique focuses on comparing the relative sizes of tasks, rather than trying to estimate the exact time required to complete them. This helps to reduce the impact of individual biases and encourages more accurate estimates.
  • Scalability: The Fibonacci sequence provides a natural scale for estimating tasks of varying complexity. As the numbers in the sequence increase, the gaps between them also increase, reflecting the greater uncertainty associated with larger tasks.
  • Encourages collaboration: Fibonacci Agile Estimation is often used in conjunction with planning poker, a collaborative estimation technique that involves the entire team. This helps to ensure that estimates are based on a broad range of perspectives and expertise, leading to more accurate and reliable results.

How to use Fibonacci Agile Estimation

Fibonacci Agile Estimation can be used in conjunction with planning poker, a popular Agile estimation technique. Here's a step-by-step guide to using Fibonacci Agile Estimation with planning poker:

  1. Prepare the Fibonacci sequence: Create a set of cards or tokens with the Fibonacci numbers (1, 2, 3, 5, 8, 13, 21, etc.) printed on them. You may also include a 0 and additional numbers, such as half-points or infinity, to represent tasks that are trivial or too large to estimate accurately.
  2. Gather the team: Invite all team members who will be working on the project to participate in the estimation session. This may include developers, testers, designers, and other stakeholders.
  3. Present the task: The product owner or project manager presents a user story or task to the team, providing any necessary context and answering questions to ensure that everyone understands the requirements.
  4. Estimate individually: Each team member selects a Fibonacci number that they believe represents the relative size of the task, keeping their choice hidden from the rest of the team.
  5. Reveal and discuss: All team members reveal their chosen numbers simultaneously. If there is a wide range of estimates, the team discusses the reasons for the differences and seeks to reach a consensus.
  6. Repeat: The process is repeated for each task or user story in the project backlog until all items have been estimated.

Once all tasks have been estimated, the team can use the Fibonacci numbers to prioritize work, allocate resources, and plan project iterations.


Fibonacci Agile Estimation is a valuable technique for estimating the effort required to complete tasks in Agile project management. By using the Fibonacci sequence to assign relative sizes to tasks, teams can improve the accuracy and consistency of their estimates, leading to better project planning and resource allocation. By incorporating this technique into your Agile practices, you can help your team deliver projects more effectively and efficiently.