Jekyll Age provides an age tag for jekyll/liquid which displays the current age in years.
Add gem "jekyll-age" to your Gemfile. For example:
group :jekyll_plugins do
gem "another-jekyll-plugin"
gem "jekyll-age"
end
Now run bundle install to install all plugins in the Gemfile.
Alternatively, add the plugin to your _config.yml file in an array with the key plugins and run gem install jekyll-age.
plugins:
- another-jekyll-plugin
- jekyll-age
In your markdown file, simply use the template tag age with a date ({% age 'YYYY-MM-DD' %}) and the plugin will output the appropriate age in years.
If you write the following markdown:
{% age '1989-12-17' %} years
The plugin will print (given that the current date is before 2019-12-17):
29 years
MIT