SprintPlan — Sprint Planning Fibonacci Calculator

A single-page calculator that converts Fibonacci story points into approximate hours and sizing guidance for a sprint. Teams enter their sprint length and daily hours to see how big each point value really is.

---

Features

• Live calculation – Changing the sprint length (weeks) or hours per day updates the table immediately.
• Points-to-hours table – Shows each Fibonacci point value with its approximate hours range (min–max) and a size label (Tiny, ~N days, Medium, Large, Very large, May not fit in your sprint, Bigger than your whole sprint).
• Sprint-relative sizing – Size labels are based on the share of the sprint a story takes up, so they stay meaningful for any sprint length.
• Auto-extending scale – Always shows 1–21 points, and adds more Fibonacci values until one whose whole hours range exceeds the sprint.
• Saved settings – Inputs are stored in the browser's localStorage, which does not expire.
• Sensible defaults – A 2-week sprint at 8 hours per day.

---

Tech Stack

• Language: HTML, vanilla JavaScript
• Frontend: Bootstrap 5.3.3 (dark theme) and Font Awesome 6.5.2, both loaded from CDNs
• Storage: Browser localStorage
• Build: Terser 5.31.6 minifies app.js during the Docker build (node:22-alpine build stage)
• Hosting: Static files, or a Docker image built on busybox:1.36-musl that serves the page with BusyBox httpd (about 2.5 MB)

---

Quick Start

Prerequisites

• A modern web browser
• Docker (optional, for the container)

Installations

Get the project

Copy or clone the project folder. There are no dependencies to install.

Development

Open index.html directly in a browser:

xdg-open index.html

Production Build

docker build -t sprintplan .
docker run -d --rm -p 8080:8080 --name sprintplan sprintplan

Visit: http://localhost:8080

Repository Structure

SprintPlan/
├── index.html      # The calculator page: markup and styles
├── app.js          # Calculation, table rendering and saved settings
├── Dockerfile      # Minifies app.js, then serves the page with BusyBox httpd on port 8080
├── .dockerignore   # Sends only index.html and app.js to the Docker build
├── docs/
│   └── screenshot.png  # README screenshot
└── README.md       # This file

Architecture Overview

Frontend

• One static page with no build step. Bootstrap and Font Awesome come from jsDelivr and cdnjs, so the browser needs internet access for styling and icons.
• app.js reads the two inputs on every input event, saves them to localStorage under the key sprintPlanSettings, and redraws the table.

Calculation

• Sprint days = weeks × 5 working days; sprint hours = sprint days × hours per day.
• 1 point = half a working day, so hours = points × (hours per day ÷ 2).
• Approx. hours is a min–max range running halfway to the neighbouring Fibonacci values (e.g. 3 points covers 2.5–4 points' worth of hours).
• Size labels by share of the sprint:

Share of sprint	Label
Whole range (min hours) over the sprint	Bigger than your whole sprint, must split
Top of range (max hours) over the sprint	May not fit in your sprint, consider splitting
More than 50%	Very large, consider splitting
35% or more	Large (~N days)
20% or more	Medium (~N days)
1 point	Tiny
Anything else	~N days

Example for a 2-week sprint at 6 hours per day (60 hours):

Points	Approx. hours	Size
1	1.5–4.5	Tiny
2	4.5–7.5	~1 day
3	7.5–12	~1.5 days
5	12–19.5	Medium (~2.5 days)
8	19.5–31.5	Large (~4 days)
13	31.5–51	Very large, consider splitting
21	51–82.5	May not fit in your sprint, consider splitting
34	82.5–133.5	Bigger than your whole sprint, must split

Deployment

Component	Platform	Notes
Calculator page	Docker (busybox:1.36-musl)	Multi-stage build minifies app.js with Terser; runs as nobody on port 8080
Calculator page	Any static host	Upload index.html and app.js together