Introduction

A system to organise your information

Johnny.Decimal is designed to help you find things quickly, with more confidence, and less stress.

You assign a unique ID to everything in your life.

These IDs help you stay organised. They impose constraints that make it harder to get lost. And you create an index to link everything together.

The system is free to use and the concepts are the same at home, work, or that club you manage.

A diagram showing the structure of a Johnny.Decimal number. The number is 15.52 and it explains how the 1 is an area, which groups related categories in sets of 10. The 15 is the category, in this case Travel. And 52 is just an ID; they start at 01. The title of this, our 52nd travel thing, is Trip to NYC.
Figure 62.11A. The anatomy of a Johnny.Decimal ID.

The problem

In real life, if you stored your stuff in piles of badly-labelled boxes you'd never find anything again.

If you put those boxes in boxes, in boxes, you'd never know which box to open to find the next box. It would be chaos. But this is how you save computer files.

Figure 62.11B. A chaotic filesystem with many levels of folders.

The solution

Here's one way to think about how Johnny.Decimal works. In this analogy, a computer is a room, an area is a filing cabinet, a category is a drawer, and an ID is a manila folder.

Step 1: Buy 10 filing cabinets

We can't store our stuff on the floor, so we buy 10 filing cabinets. Then we dedicate three of them to areas of our life – life admin, home business, and tennis club.1

Figure 62.11C. A filing cabinet for each major area of our life (diagram not to scale).

Step 2: Assign some drawers

Each cabinet has space for 10 drawers, so we categorise what we want to store. In life admin we decide on five drawers and label them: me, house, money, online, and travel. There's space for a number, so we add that too.2

Figure 62.11D. Our life admin filing cabinet has five drawers.

Step 3: File your stuff in folders

We put our documents in folders. Each folder gets a number starting at .11 so we can track them. In this case, there's some insurance documents in 15.22 Travel insurance. This folder goes in a drawer.

Figure 62.11E. Our documents are stored in numbered folders in the relevant drawer.

This is how we structure our filesystem

Let's return to our computer. The filing cabinets have become our area folders. The drawers are category folders. And the manila folders are the IDs where we save our files.

Figure 62.11F. A neat file structure with areas, categories, and IDs.

Benefits of the ID

Each of our storage folders now has a number, the Johnny.Decimal ID. It always has two digits, a decimal, and two digits. For example, 15.22 22.11 31.17. This number is really useful.

Provides structure

The ID tells us exactly where a thing is. The numbers before the decimal are the item's category, and they define the structure of your system.

At a glance, you know what sort of thing the item contains. You'll be astonished at how many of your category numbers you remember.

Easy to communicate

They're short, memorable, and can be spoken out loud. Say it like "sixteen oh-two" or "thirty-one dot seventeen".

This is really handy when you want to tell someone (including your future self) where a thing is.

Things stay put

If you use the alphabet to name folders, they move when a new one is created. So you never get a chance to develop muscle memory. Numbers solve this problem.

In the example above, 11 Me comes before 12 House because the folders sort by number. If we made a new folder, 16 Aardvark collection, nothing would move.

Imposes limits

The 'no more than 10' concept is at the heart of Johnny.Decimal.

When you start looking for something, there's no more than 10 area folders to choose from. Select one and ignore the rest. Now there's no more than 10 category folders to choose from. Repeat the process.

You arrive in a folder with no more than 100 IDs. If the ID was created recently it will have a higher number. If not, lower. And things created together, stick together. The alphabet can't ruin the party.

I like it! What next?

Welcome to the Johnny.Decimal family. Everything here is written by Johnny 👋🏼 and my partner Lucy. There's plenty to go on with.

Get organised

  • Get organised fast with our pre-built systems for Life Admin and Small Business. They're what I use to manage my life and business.
  • Want to build your own system and learn everything I know about being more organised? Johnny.Decimal University has the courses you need.

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Footnotes

  1. We don't try to use all 10 filing cabinets, there's room to grow. ↩

  2. I'll explain later why the first drawer isn't number 01 or 10. ↩