Sprint Backlog vs Product Backlog: What’s the difference?

Every product team needs to explore new ideas for the improvement of their product. However, this is not an easy task because they need an effective way to gather and evaluate their ideas and requests. Most product teams use some kind of backlog for this purpose.

The concept of backlog — a sum of things waiting to get done — is important in Agile. And our title terms — Product Backlog and Sprint Backlog — are directly connected to the Scrum Agile framework. They represent 2 out of 3 of its Artifacts, which define all the work that needs to be done during a project.

In this text, we will explain:

• What the Product Backlog is,
• What the Sprint Backlog is, 
• How they work together, and
• The differences between the two.

We’ll also provide you with examples of these backlogs so that you can more easily understand them.

What is a Product Backlog? 

According to the Scrum Guide, ”The Product Backlog is an emergent, ordered list of what is needed to improve the product. It is the single source of work undertaken by the Scrum Team.” 

No matter how big the project is, there is only one Product Backlog.

The items in the Backlog are listed according to their priority, from top to bottom. 

This list of items in the Product Backlog and their priority can change throughout the project to accommodate external changes, market shifts, or updated user requirements.

The one responsible for creating and maintaining the Product Backlog items is the Product Owner. Once they create it, they share it with both the Scrum Team and the stakeholders. The rest of the team can also contribute to the creation of the backlog.

The Product Backlog consists of all the upcoming product work including: 

• Bug fixes,
• User stories, i.e. short descriptions of a product’s features from the perspective of the user,
• New features, and 
• Changes to the already existing features.

The Product Backlog also contains the Product Goal — the overall actionable vision of the product or what the team should strive for while working on the product. 

The Product Goal serves as a guide for the Scrum team’s planning and gives the project its purpose. There should be only one Product Goal, and it should be clear and visible to everyone working on the product. 

Refining the Product Backlog

The act of breaking down and further defining and improving the Product Backlog is called backlog refinement. It keeps the Product Backlog relevant and keeps the team’s priorities straight. 

Product Backlog refinement — as the name suggests — is the process of refining and further specifying items that are contained in the Product Backlog. 

What is a Sprint Backlog?

A Sprint Backlog contains a part of the Product Backlog items, which the team is supposed to tend to in the following work period known as a Sprint.

A Sprint is a short period during which the team is focused on completing a pre-defined portion of the work on the product. 

Sprints usually last from 2 to 4 weeks. During this time, the team decides what it can deliver from the Product Backlog to achieve the Sprint Goal. 

The Sprint Goal is a goal that should be achieved during the Sprint. It is a short description of the strategy for achieving that Sprint’s objective. The Product Owner and the Development Team are the ones responsible for formulating the Sprint Goal.

Through Sprints, ideas are turned into value.

Developers are the ones who create the Sprint Backlog and decide which items will be developed during a Sprint.

Sprints should only contain tasks Developers believe can be performed within that time frame. Each Sprint has its own Sprint Goal and a list of prioritized tasks that need to be completed to achieve that goal.

The Sprint Backlog should be accessible to all team members to receive information about the progress of the project.

A common belief is that a Sprint Backlog is not susceptible to change because that would impair the team’s ability to focus on the Sprint Goal. However, according to Scrum.org, a Sprint Backlog can change. It is flexible as long as it does not distract the team from concentrating on the Sprint Goal — which cannot be changed during the Sprint. 

Sprint Backlog consists of user stories and task descriptions. 

How do Sprint Backlog and Product Backlog work together?

The Scrum Team must fully understand what each of these backlogs represents to be able to function properly.

These backlogs are 2 out of 3 Scrum Artifacts, the third one being Increments. They all define what needs to be done by the team. 

Scrum Artifacts act like a funnel — distilling Product Backlog items into Sprint Backlog tasks, and the fruits of these Sprints into Increments, i.e. stable and usable versions of the product.

This distillation process starts with a Sprint Planning meeting.

During the Sprint Planning meeting, the team decides on the items from the Product Backlog that will be completed during the following Sprint and the ways to complete them, accounting for any potential roadblocks.

The items from the Product Backlog that are of the highest priority are added to the Sprint Backlog. Afterward, the items on the Sprint Backlog list are refined into smaller steps or tasks that should be done to complete the item from the list.

It’s important that these steps or tasks are clearly communicated so that the team can execute them. All team members should take part in deciding which backlog items will be worked on in the upcoming Sprint.

What’s the difference between the Product Backlog and Sprint Backlog?

In case there’s still some lingering confusion about the difference between the Product and Sprint Backlogs, the following side-by-side comparison should make everything crystal clear.

	Product Backlog	Sprint Backlog
Purpose	To determine the features that should be worked on during the entire project and decide on the priorities	To determine the part of the Product Backlog that should be worked on during a single Sprint
Contents	A master list that contains all tasks for the ongoing project	A batch of the product backlog items with tasks that need to be completed during the Sprint
Ownership	It is owned by the Product Owner.	It is owned by the entire Scrum Team.
Creation	It is created by the Product Owner, often with the help of others in the Scrum Team.	It is the Developers’ responsibility.
Commitment	Product Goal	Sprint Goal
Dependency	It is dependent on the product roadmap and requirements.	It is dependent on the product backlog.
Completion	It lasts until the project is finished.	It lasts from 2 to 4 weeks.

Project Backlog example

To reiterate, a Product Backlog should contain a prioritized list of everything that goes into the project. It can change and morph over time and should always be accessible to everyone on the team. 

For this reason, the most optimal place to keep your Product Backlog is a collaborative project management tool where you can:

• Have your entire team in one place,
• Create an unlimited number of tasks and boards,
• Customize your boards and create a Product Backlog that perfectly fits your project,
• Invite guest members,
• Customize permissions for each board, and
• Notify your team about all changes that happen to tasks they’re subscribed to.

Here’s an example of how a Product Backlog may look in Plaky’s table view. 

A well-organized Product Backlog should contain no more than 100 to 150 items. Any more than that would only complicate things instead of making them more organized. 

Keep in mind that not all of these items should be described in detail. 

Since the Product Backlog is bound to change throughout the project, trying to define every single item would only be a waste of time. Instead, try to define only those items that are likely to go into the next 2 to 3 Sprints.

Sprint Backlog example

Once the items from the Product Backlog are fully defined and marked as ready for development, they can be transferred from the Product Backlog to the Sprint Backlog. 

Here’s an example of a Sprint Backlog created with items from the Product Backlog in the image above.

The Sprint Backlog should contain any number of items, as long as they can be reasonably completed over the course of that one Sprint. Once the items are transferred into the Sprint Backlog and assigned to the right people, the work can begin.

Conclusion: Product and Sprint Backlogs organize and prioritize work in Scrum projects

Both Product and Sprint Backlogs are necessary for the proper functioning of the project in Scrum.

The Sprint Backlog cannot exist without the Product Backlog, whereas the Product Backlog is made based on the product requirements and roadmap. 

These backlogs help divide the work into smaller parts that make it more manageable and easier to navigate. 

Hopefully, this blog post has made the difference between them clearer.

✉️ Do you have any additional questions about the Product Backlog and Sprint Backlog? Would you like to add something? If so, feel free to contact us at blogfeedback@plaky.com, and we may include some of your ideas in this or our future blog posts. Also, if you liked this blog post and found it useful, share it with someone who will benefit from it!