Ruby Color Contrast Checker

CLI interface for checking WCAG2.0 Color Contrast Ratio in Ruby.

           

---

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.

Demo

Installation

Install the gem:

$ gem install ruby_color_contrast_checker

Usage

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

Development

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.

Contributing

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.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

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.

🌟 Special Thanks

• Richard Bates for the blog post on releasing a gem.