Check if the 2 colors provided pass the AA and AAA Levels (including for Large Text and Icons), according to WCAG 2.1 guidelines.
Further information can be found here.
In summary:
- Level AA : Ratio >= 4.5
- Level AA (Large) : Ratio >= 3.0
- Level AAA : Ratio >= 7.0
- Level AAA (Large) : Ratio >= 4.5
Note:
Large is for regular text with 18pt or larger, or bold text with 14pt or larger.
Logo generally fall into the large category.
It is recommended to fulfill at least Level AA for your projects.
Install the gem:
$ gem install ruby_color_contrast_checker
Run the contrast_checker
executable:
$ contrast_checker
------------------------------------
| Welcome to Color Contrast Checker |
------------------------------------
\ ^__^
\ (oo)_______
(__)\ )\/\
||----w |
|| ||
Enter the first hex color string:
> #000000
Enter the second hex color string:
> #FFFFFF
Contrast Ratio : 21
Level AA : PASS
Level AA (Large) : PASS
Level AAA : PASS
Level AAA (Large) : PASS
After checking out the repo, run bin/setup
to install dependencies. Then, run rake spec
to run the tests. You can also run bin/console
for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install
.
Bug reports and pull requests are welcome on GitHub at https://github.com/cheehwatang/ruby_color_contrast_checker. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.
The gem is available as open source under the terms of the MIT License.
Everyone interacting in the Ruby Color Contrast Checker project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.
- Richard Bates for the blog post on releasing a gem.