# ISO dates

## Overview

When applying dates to digital file names, the International Organization for Standardization (ISO) date format is recommended. This is a standard way to communicate a date that is understood globally, both by humans and computers. It is also known as [ISO 8601](https://www.iso.org/iso-8601-date-and-time-format.html).

## Why use ISO dates?

The aim in using a standard format is to eliminate confusion (especially around the different way dates are represented in the USA compared to Europe, for example) and to make your files more easily searchable and sortable. The specific format is year first, followed by month then day. Each of these is separated by a hyphen, with numbers less than 10 preceded by a zero. By using this format, you will be able to sort your digital files more easily into chronological order.

For example: 3 June 2022 = 2022-06-03

Big tip: There are no spaces!

Your file names may end up looking something like this:

2020-12-01\_participants-list.xml

2022-06-03\_interview.doc

2022-07-03\_analysis.r

Remember that computer file systems have a specific way of sorting files. If your file names all start with an ISO date, they will automatically sort from oldest to newest using the default alphabetical sort. Any other date-based naming convention would create different results.

## Helpful resources

[The Problem with Dates](https://www.researchgate.net/publication/327519043_The_Problem_with_Dates_Applying_ISO_8601_to_Research_Data_Management)

[W3C Date and Time Formats](https://www.w3.org/TR/NOTE-datetime)

[Organising Your Data](https://www.data.cam.ac.uk/data-management-guide/organising-your-data)

[Project Structure](https://slides.djnavarro.net/project-structure/#1)
