Agile Burndown Calculator
Track sprint progress and forecast whether your team will finish on time. Enter story points, days elapsed, and velocity trend to see your projected completion day.
About this calculator
A burndown chart measures how quickly a team is consuming story points relative to the sprint timeline. The core idea is to compare remaining work against current daily velocity, adjusted for any upward or downward velocity trend. First, remaining points are found with: remainingPoints = totalStoryPoints − completedPoints. Daily velocity is computed as: dailyVelocity = completedPoints / daysElapsed. The projected completion day is then: projectedCompletionDay = ⌈remainingPoints / (dailyVelocity × velocityTrend)⌉ + daysElapsed. If this value exceeds the sprint length, the sprint is at risk of not completing on time. The velocityTrend multiplier (e.g., 0.9 for slowing, 1.1 for accelerating) lets teams account for real-world momentum changes.
How to use
Suppose a team has 40 total story points, has completed 15 points in 3 days, with a sprint length of 10 days and a velocity trend of 1.0. Step 1 — Remaining points: 40 − 15 = 25 points. Step 2 — Daily velocity: 15 / 3 = 5 points/day. Step 3 — Days to finish remaining work: ⌈25 / (5 × 1.0)⌉ = 5 days. Step 4 — Projected completion day: 5 + 3 = day 8. Since 8 ≤ 10, the sprint is on track to complete within the sprint window.
Frequently asked questions
What is a good velocity trend value to enter for an agile burndown calculation?
A velocity trend of 1.0 means the team is maintaining its current pace. Values above 1.0 (e.g., 1.1) indicate the team is accelerating, while values below 1.0 (e.g., 0.85) signal a slowdown. Most teams use historical sprint data to estimate this multiplier. If you have no prior data, start with 1.0 as a neutral baseline and adjust after your first sprint.
How does the burndown calculator predict whether a sprint will complete on time?
The calculator divides remaining story points by the adjusted daily velocity (velocity × trend) to estimate how many more days are needed, then adds the days already elapsed. If the result exceeds the sprint length, it flags the sprint as unlikely to complete on time. This gives Scrum Masters and Product Owners an early warning signal rather than discovering the shortfall on the last day.
Why do remaining story points sometimes increase mid-sprint on a burndown chart?
Story points can increase mid-sprint when new scope is added, when tasks are re-estimated upward after discovery of hidden complexity, or when bugs are logged as new work items. This is called 'scope creep' on the burndown chart and appears as an upward step rather than a downward slope. Tracking these increases helps teams have honest conversations about sprint commitment and backlog grooming quality.