When comparing D3 Gallery vs Hackr.io, the Slant community recommends Hackr.io for most people. In the question“What are the best resources to learn D3.js?” Hackr.io is ranked 4th while D3 Gallery is ranked 5th. The most important reason people chose Hackr.io is:
Instead of getting a recommendation from a single dev, you get recommendation from the entire programming community.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Updated often
The gallery is updated frequently with improvements and new examples.
Pro A lot of visual appealing examples including source code
There are hundreds of examples to look at, including the source code. This will give you a great idea of what D3.js is capable of.
Pro Community trust
Instead of getting a recommendation from a single dev, you get recommendation from the entire programming community.
Pro Recommendation for every programming language/framework/library
You can find Python as well as Jenkins.
Pro Nice filters
Free, Video, Book, Beginner, Advanced, etc.
Cons
Con Examples only
The D3 gallery isn't a tutorial, it only shows examples of graphs created with D3.
For someone completely new to D3, this would likely be an overwhelming place to start.