Every Project Manager knows the frustration of trying to answer a simple question: “How is the project really doing?” The answer usually involves opening multiple tools, cross-referencing spreadsheets, and mentally stitching together information scattered across GANTT charts, status reports, and backlog trackers. By the time you’ve assembled the picture, the meeting is half over and your audience has lost the thread. The problem isn’t a lack of data, but that traditional visualizations each tell only part of the story. GANTT charts excel at showing timelines and dependencies, but they obscure how effort is distributed across the project. A hundred small tasks and one massive epic look roughly the same when rendered as horizontal bars. Work Breakdown Structure (WBS) trees show hierarchy, revealing how deliverables decompose into work packages, but they treat every box as equal regardless of whether it represents two days of work or two months. Pie charts can show proportions, but they flatten everything into a single level, losing the hierarchical context that makes project data meaningful.
This is where Sunburst diagrams offer something different. Originally popularized for visualizing file system usage and organizational structures, the Sunburst format turns out to be remarkably well-suited for project management, once you map the right data to its visual properties.
Mapping project data to visual properties
The approach I implemented for automating the reporting of project status as a Sunburst visualization rests on three core mappings that transform abstract project data into immediate visual insight.
First, hierarchy maps to concentric rings. The center of the diagram represents the project root, whether that’s a Program, Portfolio, or top-level Initiative. Each successive ring moving outward represents a deeper level in the work breakdown structure: Initiatives give way to Epics, Epics to Stories, Stories to Tasks. This radial layout preserves the parent-child relationships that define project structure while keeping everything visible in a single view. You can trace any piece of work back to its parent by following the arc inward toward the center.
Second, arc size encodes effort. This is where the Sunburst format diverges from traditional WBS trees. Each segment’s angular width is proportional to its estimated effort, whether measured in story points, person-days, or hours. A segment representing 40 story points of work takes up twice the angular space of a 20-point segment. This proportional sizing makes scope distribution immediately visible. You don’t need to sum up numbers in a spreadsheet to see that one Initiative is consuming half the project’s effort, it literally takes up half the circle.
Third, color signals completion status. Rather than using color for arbitrary categorization, Sunburst diagrams encode the state of each work item (done, in-progress, blocked, or backlog) through a consistent color scheme. Green segments represent completed work. Yellow or orange indicates work in progress. Red flags blocked items. Gray shows backlog items not yet started. The result is a project health heat-map layered onto the structural view. Healthy branches of the project glow green; troubled areas stand out in red and orange.
What the Sunburst diagram reveals
When these three mappings combine, a single image answers questions that typically require drilling through multiple reports and mentally aggregating information.
Where is effort concentrated? Large arcs immediately draw the eye, showing which Initiatives or Epics dominate the project scope. If one branch of the project consumes 60% of the total effort, that’s visible at a glance, no calculation required. This makes scope imbalances obvious in a way that lists and tables cannot.
Which areas are falling behind? When you see a large arc filled predominantly with red and orange rather than green, you’ve found a problem area. The combination of size (this is a significant chunk of work) and color (it’s not getting done) tells a story that would otherwise require correlating effort estimates with status reports.
Is scope balanced across initiatives? The symmetry or asymmetry of the diagram reveals whether effort is distributed as intended. A project with four supposedly equal initiatives should show four roughly equal quadrants. If one initiative has ballooned to dominate the view, that’s a conversation worth having.
How much of the project is actually in progress versus sitting in the backlog? The overall color distribution across the diagram shows the ratio of completed, active, and pending work. A diagram that’s mostly gray signals a project that hasn’t really started despite perhaps having a few visible activities. A diagram trending toward green shows genuine progress.
Tracking change over time
Static snapshots are useful, but projects are dynamic. Scope changes. Priorities shift. Work gets added, removed, or re-estimated. Understanding how a project has evolved often matters as much as understanding its current state.
The tooling I created addresses this by generating Sunburst history visualizations. By comparing snapshots taken at different points, equally spaced in time, the tool creates a visual record of how project structure and completion status have changed. You can see scope creep manifesting as new segments appearing in outer rings. You can watch progress ripple through the diagram as segments shift from gray to yellow to green over successive snapshots.This temporal view makes patterns visible that are nearly impossible to detect in spreadsheet comparisons. A project that’s been “80% complete” for three months looks very different when you can see that the remaining 20% keeps growing as fast as work gets completed. Conversely, a project that feels slow might reveal steady, healthy progress when viewed as a sequence of Sunburst diagrams.
When Sunburst diagrams work best
Like any visualization, Sunburst diagrams have their sweet spot. They work best for executive portfolio reviews, where stakeholders need a high-level, proportional view of project health without getting lost in details. They’re valuable in sprint retrospectives for showing what got done versus what remains. They shine in scope discussions, making it clear where effort is being allocated and whether that matches strategic intent. And they’re excellent for identifying imbalanced work-streams, those areas where effort has quietly accumulated beyond what anyone intended. Sunburst diagrams complement rather than replace other visualizations. GANTT charts remain essential for scheduling and dependency management. WBS trees are still the right tool for detailed breakdown and task assignment. But when you need to communicate project health, scope distribution, and structural hierarchy in a single view, especially to an audience that doesn’t have time to parse detailed reports, the Sunburst format offers something that traditional project management visualizations cannot match.
