Hill Charts: See Where Projects Really Stand
Hill charts let you see where a project really stands by plotting progress as an upside-down bell curve, where the left side is exploration (figuring out what to do) and the right side is execution (doing it). You enter the current position of each task or workstream on the hill, and the chart shows whether you are still climbing (unknowns remain) or descending (the work is mostly defined and being completed). This article explains how hill charts work, how to read them, and how to use them without falling into common traps.
What a Hill Chart Actually Shows
A hill chart is a visual tool popularized by Basecamp (the software company) to answer the question “where does this really stand?� without the false precision of a percentage. Instead of saying “we’re 70% done,� you place a dot on a hill. The left slope is where you are climbing—you are still learning, prototyping, and discovering what needs to be built. The right slope is where you are descending—you know exactly what to do and are just doing it. The top of the hill is the point where uncertainty has been resolved; you have a clear plan and now it’s about execution.
The key insight is that progress is not linear. A task can be 50% up the left side (you’ve done a lot of thinking) but still have huge unknowns. Conversely, a task can be at the very top of the hill and be considered “almost done� because the remaining work is purely mechanical. Hill charts make that distinction visible.
How to Build and Update One
You don’t need special software—a spreadsheet or a whiteboard works. The steps are:
- List the major tasks or workstreams (not every tiny subtask).
- Draw a bell-shaped curve for each task, or one shared curve with dots.
- Place a dot on the curve for each task based on your judgment: is this task still in the “figuring out� phase (left side) or the “doing� phase (right side)?
- Update the dots regularly (e.g., weekly) during team check-ins.
- Discuss why a dot moved up or down—the discussion is more valuable than the chart itself.
The vertical position is not a percentage complete; it’s a measure of clarity. A dot at the bottom of the left side means “we haven’t started and we don’t know what we’re doing.� A dot at the top means “we know exactly what to do.� A dot at the bottom of the right side means “we’re executing and almost finished.�
Common Mistakes and Misconceptions
The most common mistake is treating the hill as a time-based Gantt chart. The x-axis is not time; it’s confidence. A task can stay at the same horizontal position for weeks while you work on it, because you still don’t know what you’re doing. That’s honest. Another mistake is placing a dot at the top of the hill too early—when you think you understand the problem, but you haven’t validated it. The top of the hill should be the moment when the approach is locked, not when you feel optimistic.
A related misconception is that a task on the right side is “almost done.� Actually, a task just over the top is still a long way from completion—it’s just that the remaining work is predictable. The right side can be long, especially for tasks with a lot of implementation detail. The hill’s width is not fixed; you can stretch it to reflect the amount of work.
Hill Charts vs. Other Progress Tools
Hill charts are often compared to burndown charts, Kanban boards, and percentage-complete reports. Burndown charts show remaining work over time, but they assume the work is well-defined and that “done� is clear. Kanban boards show status (to-do, doing, done) but not the quality of progress—a task can be “in progress� for months without clarity. Percentage-complete reports are notoriously subjective and often overestimated. Hill charts fill a gap: they show the nature of the remaining work, not just the quantity.
However, hill charts are not a replacement for a project schedule. They don’t show deadlines, dependencies, or resource allocation. They are a communication tool, not a planning tool. Use them alongside a traditional project plan if you need dates and critical paths.
When to Use (and Not Use) a Hill Chart
Hill charts work best for knowledge work—software development, product design, research, marketing campaigns—where tasks involve discovery and creativity. They are less useful for repetitive, well-understood work like manufacturing or data entry, where a simple checklist is sufficient. They also require a team that is comfortable with ambiguity and honest about uncertainty. If your culture punishes admitting you don’t know something, the chart will be a lie.
Use hill charts during weekly status updates to spark conversation. Ask “Why is this dot still on the left side?� or “What would it take to get it over the top?� The chart is a starting point for a conversation, not a report card.
Limitations and Pitfalls
Hill charts are subjective by design. Two people can look at the same task and place it at different points. That’s okay—the discussion that follows is valuable. But if you need objective, measurable progress, hill charts won’t give it to you. They also don’t scale well for very large projects with hundreds of tasks; you’ll need to group tasks into workstreams. Finally, they can become stale if not updated regularly. A hill chart that is not reviewed weekly quickly becomes fiction.
Frequently Asked Questions
What does the top of the hill mean exactly?
The top of the hill is the point where you have enough understanding to proceed with confidence. You know what to build, how to build it, and what “done� looks like. It does not mean the task is half done in terms of effort; it means the uncertainty is resolved.
How do I decide if a task is on the left or right side?
Ask: “Do we still have open questions that could change what we build?� If yes, it’s on the left. If you have a clear plan and are executing it, it’s on the right. If you’re in the middle, you might be at the top—but be honest about whether you’ve truly validated your approach.
Can a task move backwards on the hill?
Yes. If you discover a new unknown during execution, the dot should move back to the left side. This is a feature, not a bug—it reflects reality. Many teams find that tasks often roll back when they hit an unexpected technical challenge or a change in requirements.
Is a hill chart the same as a burndown chart?
No. A burndown chart shows remaining work over time and assumes the work is well-defined. A hill chart shows the level of understanding or confidence, not time. They answer different questions: burndown answers “how much is left?� while hill answers “how sure are we about what’s left?�
Do I need special software to create a hill chart?
No. You can draw one on a whiteboard, use a spreadsheet with a scatter plot, or use a dedicated tool like Basecamp’s hill chart feature. The value is in the conversation, not the tool.
How often should I update the hill chart?
At least once a week, during a regular team check-in. More frequent updates are fine if the team is highly dynamic. The key is to make it a habit so the chart stays honest and useful.
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