Johnny Decimal + PARA Organization System

A hybrid system combining Johnny Decimal structure with PARA methodology.

Structure

AC.ID — Title
│
├── AC   = Area (10-99) + Category (X0-X9)
└── ID   = Unique identifier within category (01-99)

PARA Mapping

| JD Area | PARA | Purpose | | ------- | --------- | --------------------------------------- | | 10-19 | Projects | Active projects with a defined outcome | | 20-29 | Areas | Ongoing responsibilities to maintain | | 30-39 | Resources | Reference materials, topics of interest | | 90-99 | Archives | Completed or inactive items | | Inbox | — | Items to process and organize |

Project Numbering

Projects use a year-based ID format:

10.{YY}{NNN} — Project Title
     │  │
     │  └── NNN = Sequential number (001, 002, ...)
     └───── YY  = Year (25 for 2025)

Example: 10.25001 — Website Redesign (first project of 2025)

Rules

• Categories subdivide areas (11, 12, 13...) — max 10 per area
• IDs are unique items within a category (11.01, 11.02...)
• Projects use 10.{YY}{NNN} format with year prefix
• Keep one location per ID — no duplicates
• Use descriptive titles after the number
• Move completed projects to 90-99 Archives

File Naming Convention

Files inherit their prefix from the folder path:

{Category} - {Subcategory} - {Date} - {Description}.{ext}
    │            │             │           │
    │            │             │           └── Free-form description
    │            │             └── ISO date YYYY-MM-DD (optional)
    │            └── From parent folder name (e.g., "27.05 - Fiscalité" → "Fiscalité")
    └── From grandparent folder name (e.g., "27 - Finances" → "Finances")

Examples

| Folder Path | File Name | | -------------------------------------- | ---------------------------------------------------------- | | 27 - Finances/27.05 - Fiscalité/ | Finances - Fiscalité - 2024-04-15 - Déclaration 2042.pdf | | 23 - Sport/23.01 - Tir à l'arc/ | Sport - Tir à l'arc - 2024-09-14 - Licence FFTA.pdf | | 34 - Administratif/34.03 - Identité/ | Administratif - Identité - Passeport.pdf |

Rules

• Separator: - (space-dash-space)
• Date: Optional, ISO format YYYY-MM-DD
• Description: Title Case, accents allowed
• No date for reference documents (rules, templates)

Best Practices

• Start simple — add categories only when needed
• Use consistent naming conventions across all items
• Prefer flat structures over deep nesting
• Keep Inbox at zero — process and file items regularly

Index Location

The Johnny Decimal index is maintained in Apple Notes. Use the mcp_apple-notes tools to search or consult the index when needed.