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Sprint Velocity & Capacity Forecast

Forecast sprint capacity and release timelines with velocity variance. Enter values for instant results with step-by-step formulas.

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Frequently Asked Questions

What is sprint velocity?

Velocity is the amount of work (story points) a team completes per sprint on average. Measured empirically: Sum completed points over last 3-6 sprints, divide by sprint count. Example: Team completed 35, 42, 38, 45 points over 4 sprints. Velocity = (35+42+38+45)/4 = 40 points/sprint. Use for forecasting: 200-point backlog at 40 velocity = 5 sprints. Important: Velocity is team-specific—don't compare across teams. A '40-velocity' team isn't faster than '30-velocity' team; they estimate differently. Track trend, not absolute number.

How do I calculate sprint capacity?

Capacity = Available work hours for the sprint. Formula: (Team members × Work days × Hours/day) - PTO - Meetings - Other commitments. Example: 6-person team, 10 work days, 8 hrs/day = 480 hrs total. Minus: 2 days PTO (16 hrs), 10 hrs meetings/person (60 hrs), 20% buffer (80 hrs). Available: 480 - 16 - 60 - 80 = 324 hrs. If velocity is 40 points at full capacity, adjusted = 40 × (324/480) = 27 points. Use capacity to adjust velocity when team has unusual sprint (holidays, on-call, training).

How many sprints of data do I need for reliable velocity?

Minimum 3 sprints, ideally 6-8 for reliable average. Early sprints (1-2): Velocity unstable—team forming, learning, calibrating estimates. Mid-term (3-5): Pattern emerges, use average with caution. Mature (6+): Reliable baseline; use standard deviation for confidence range. New teams: Start with capacity-based planning (hours available), transition to velocity after 3 sprints. Warning: Major changes (team composition, tech stack, product area) reset velocity—treat as new team.

What is a good velocity for a team?

No universal 'good' velocity—it's team-specific. Factors: (1) Estimation calibration (some teams use 1-5 scale, others 1-100), (2) Story granularity (big stories = fewer points completed), (3) Team skill and domain experience, (4) Technical debt and code quality. Benchmarks (rough): 5-10 points per person per 2-week sprint is common. So 6-person team: 30-60 points. But a team doing 25 points of well-estimated, high-quality work is better than 80 points of poorly-scoped, buggy work. Focus on trend (improving?) and predictability (consistent?), not absolute number.

How do I handle velocity variance in forecasting?

Use range, not single number. Calculate standard deviation of last 6 sprints. Example: Velocities 35, 42, 38, 45, 40, 36. Mean: 39.3. Std dev: 3.6. Forecast: 39 ± 4 (pessimistic 35, optimistic 43). For 200-point backlog: Pessimistic: 200/35 = 6 sprints. Expected: 200/39 = 5 sprints. Optimistic: 200/43 = 5 sprints. Communicate range to stakeholders: 'We'll complete in 5-6 sprints, most likely 5.' High variance (>25% of mean) signals estimation problems or scope instability—address root cause.

Should velocity increase over time?

Not necessarily—stable is often better than increasing. Velocity growth reasons: Team gelling, better tools, reduced tech debt, clearer requirements. Velocity plateau: Team at sustainable pace, complexity matches estimates—this is healthy. Velocity decline: Burnout, increased complexity, technical debt accumulation, team changes. Warning signs: Pressure to 'increase velocity' leads to gaming (inflating points) or cutting quality. Better metric: Value delivered (features shipped, customer impact) not points completed. Sustainable, predictable velocity > artificially high velocity.

Background & Theory

The Sprint Velocity & Capacity Forecast Planner applies the following established principles and formulas. Physics is the fundamental natural science concerned with matter, energy, and the interactions between them. Classical mechanics, founded on Newton's three laws of motion, provides the framework for analyzing the motion of objects. The first law states that an object remains at rest or in uniform motion unless acted upon by a net external force. The second law quantifies this relationship: F = ma, where force equals mass times acceleration in SI units of newtons (N = kg·m/s²). The third law establishes that every action produces an equal and opposite reaction. Kinematics describes motion without reference to its causes. The four fundamental equations relate displacement s, initial velocity u, final velocity v, acceleration a, and time t: v = u + at, s = ut + ½at², v² = u² + 2as, and s = ½(u + v)t. These assume constant acceleration and are foundational for solving projectile motion, free fall, and linear dynamics problems. Energy conservation underpins much of physics. Kinetic energy is KE = ½mv², where m is mass in kilograms and v is speed in meters per second. Gravitational potential energy is PE = mgh, where g ≈ 9.81 m/s² near Earth's surface and h is height in meters. The work-energy theorem states that the net work done on an object equals its change in kinetic energy: W = ΔKE. Electricity and circuits rely on Ohm's law: V = IR, where voltage V is in volts, current I in amperes, and resistance R in ohms. Electrical power is P = IV = I²R = V²/R, measured in watts. Wave mechanics connects frequency f, wave speed v, and wavelength λ through f = v/λ, with frequency in hertz (Hz). Pressure is defined as force per unit area, P = F/A, in pascals (Pa = N/m²). The ideal gas law PV = nRT links pressure, volume, moles n, the gas constant R = 8.314 J/(mol·K), and absolute temperature in kelvin. Gravitational force between two masses follows Newton's law of universal gravitation: F = Gm₁m₂/r², where G = 6.674×10⁻¹¹ N·m²/kg² is the gravitational constant.

History

The history behind the Sprint Velocity & Capacity Forecast Planner traces back through the following developments. The history of physics spans over two millennia, beginning with the natural philosophy of ancient Greece. Aristotle (384–322 BCE) proposed that all matter consisted of four elements and that objects moved toward their natural place, with heavier objects falling faster than lighter ones. While largely incorrect, his systematic approach to explaining nature dominated Western thought for nearly 2,000 years. The Scientific Revolution overturned Aristotelian physics. Galileo Galilei (1564–1642) performed groundbreaking experiments on inclined planes and falling bodies, demonstrating that all objects fall with the same acceleration regardless of mass, and established the principle of inertia. His use of mathematics to describe motion was revolutionary. Isaac Newton synthesized these developments in his landmark Principia Mathematica (1687), laying out the three laws of motion and the law of universal gravitation. Newton's framework unified terrestrial and celestial mechanics, explaining planetary orbits with the same equations governing a falling apple. His calculus provided the mathematical language for expressing rates of change. The 19th century brought two major theoretical achievements. James Clerk Maxwell formulated his equations of electromagnetism between 1861 and 1862, unifying electricity, magnetism, and optics, and predicting the existence of electromagnetic waves traveling at the speed of light. Thermodynamics was developed by Carnot, Clausius, and Kelvin, establishing the laws governing heat, work, and entropy. The 20th century produced two revolutions that fundamentally altered the classical picture. Albert Einstein published the special theory of relativity in 1905, showing that space and time are not absolute but relative to the observer, and that mass and energy are equivalent via E = mc². His general theory of relativity in 1915 reinterpreted gravity as the curvature of spacetime. Simultaneously, quantum mechanics emerged from the work of Planck, Bohr, Heisenberg, and Schrödinger, revealing that at atomic scales energy is quantized and particles exhibit wave-particle duality. These developments culminated in the Standard Model of particle physics, which describes all known fundamental particles and three of the four fundamental forces.

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