What are the 4 types of sprint races?

In Scrum, there are four primary types of sprints: Feature Sprint, Bug Fix Sprint, Research Sprint, and Maintenance Sprint. Each serves a distinct purpose in your development cycle, and most teams rotate through all four depending on what the product needs in a given iteration.

Feature Sprint

A Feature Sprint delivers new functionality. These run 1 to 4 weeks and aim to produce a potentially shippable product increment. Your team prioritizes features based on business value and customer needs. Most teams spend 60-70% of their sprints here, building the capabilities that drive adoption.

Bug Fix Sprint

Bug Fix Sprints address defects or issues found during previous sprints or in production. They maintain product quality and user trust. You'll run one after a major release or when your defect backlog grows faster than your feature work. The key difference from Feature Sprints: the goal isn't new capability, it's stability.

Research Sprint

Research Sprints, sometimes called Spike Sprints, explore new technologies, design approaches, or user requirements. They reduce uncertainty before committing to larger work. Duration varies based on what you're investigating. A Certified Scrum Master (CST) we trained last year used a 3-day Research Sprint to evaluate a migration path before a 6-week Feature Sprint. That decision saved the team weeks of rework.

Maintenance Sprint

Maintenance Sprints improve existing features, optimize performance, or refactor code. They keep your product maintainable and scalable over time. Without them, technical debt compounds and velocity drops. Most teams allocate 10-20% of capacity here.

When to use each type

You don't pick one and stick with it. Healthy teams rotate based on what the product needs. If you're shipping a new product, you'll run mostly Feature Sprints. If you've hit production and users are reporting issues, a Bug Fix Sprint comes next. If your team is uncertain about the next big feature, a Research Sprint buys clarity.

The Scrum Guide doesn't mandate these four types, but they map cleanly to the work most teams actually do. If you want to dig deeper into how sprints fit into your broader Agile workflow, see our guide on what is the definition of a sprint. And if you're comparing Agile to other approaches, Agile vs Waterfall shows why sprint-based work outpaces linear planning in most contexts.