Kreider uses a Google map as the main platform and, based on Census Bureau data, uses different colored tiles to show the populations of various racial groups - American Indian, Black, Asian, Hispanic, Multi-Racial, Nonwhite, Other and White - by county, census tract or block.
Household-income information can be found on the map by census tract or by block.
Kreider, a Vancouver, Canada, native whose parents are American, said he started work on JusticeMap.org in the fall for two reasons.
The "cause of economic and racial injustice and nobody else had done it [before]," said Kreider, a staffer with the environmental group Energy Justice Network.
He hesitantly chuckles as he finds the words to further explain: "I want a small piece of Internet fame. I don't know if that [will] ever happen, but it's fun to have thousands of people visit your website. It feels like you're helping people."
Kreider said he hopes regular folks, business owners and journalists, among others, use the site, which launched last month and has attracted 2,000 visitors.
What Kreider is doing "is taking the information from experts and relaying it to people who live in the neighborhoods," said Ellen Miller, executive director of Sunlight Foundation, a government transparency advocacy group and the funder of Kreider's JusticeMap.org idea.
All the information he has posted is public and free. Google offers something like it to businesses for a fee, Kreider said. But no one had ever organized this information in a simple format.
Kreider applied to about six nonprofits for grants to fund his vision, but only the Washington, D.C.-based Sunlight Foundation came through with a $10,000 award.
The foundation each year issues about 15 OpenGov Grants of $5,000 and $10,000 to those with an idea to combine government data and technology.
Kreider's idea "just fit into that perfectly," Miller said. The map is "accessible and easy to understand," she said.
Information such as racial data is important but not everyone may know how to access it.
"If you're sophisticated enough to get it from the Census Bureau that's great. But the majority of people don't have that much sophistication," Miller said.
Last weekend's fatal fire in Southwest Philadelphia on Gesner Street near 65th "was in an area of Philly that is perhaps the most equally split between blacks (70-80 percent) and Asians (20-30 percent), and a smaller number of Hispanics (0-10 percent)," Kreider wrote in an email. "Though no Asians live (as of 2010) on the exact block of the fire."
Gesner Street is also on the edge of a very poor census tract, he added. The median $20,000 household income "is the poorest census tract in Southwest Philly," Kreider said.
He may have a new idea, too.
"I wonder if anyone has made a map of where fires occur, and especially where there are injuries and fatalities, contrasting that to income and race," Kreider wrote.
On Twitter: @ReginaMedina