About Redistricter

Redistricter is at it's core a visualization tool. While I do think that the front-end of redistricter does a great job at presenting data, it's not what I consider the most important part of Redistricter. What's special about Redistricter is the back-end that can process large amounts of input data and reformat it into something that can be read client-side into the interactive map you see on your browser. You can experiment with the back-end by using the upload page to visualize your own maps. This back-end is what I consider the base of Redistricter and because of its potential to process and visualize all sorts of geographic data, I'm continually experimenting with and explore its potential applications (even beyond redistricting).

About me

My name is Colin Miller and I'm a student studying Computer Science at the University of Portland with an interest in maps and politics. I created this for a personal/school project but it went much further than I initially expected. If you have any questions, suggestions, or bug reports, feel free to email me at colin@redistricter.com or DM me on Twitter at @Redistricter.

Redistricting Terminology

PVI (Partisan Voting Index)

PVI is intended to estimate how a district would vote in an election where both parties recieved 50% of the vote. The PVI for redistricter is calculated by how a district voted in the 2020/2016 presidential elections. 1/3 of the PVI is attributed to how a district voted in 2016 and 2/3 how a district voted in 2020. The PVI is shifted slightly in favor of republicans to account for democrats' popular vote advantage in both elections.

VRA (Voting Rights Act)

The Voting Rights Act of 1965 is a federal law that applies to redistricting in every state. It mandates that some districts be drawn in a way to more accurately represent racial/ethnic minorities. A good explanation of how the VRA effects redistricting written by NYU law professor Rick Pildes can be found here. When drawing districts I tried my best to keep all maps compliant of the VRA as I could best understand it. However, interpretations of the law can vary significantly so some maps (particularly the gerrymandered maps) may be compliant of some interpretations but not others.

VAP (Voting Age Population)

A statistic detailing the population in a state or district over the age of 18. Often used to determine the voting power of various racial/ethnic groups and whether a district is compliant with the VRA.


Support Me

Redistricter's server hosting isn't free! If you want to support my work you can donate to me here.


Huge thanks to the following people for supporting my work:

  • North Texas Democrats
  • Francine Ly for Texas
  • Anonymous
  • Additional Credits

  • The visualizations wouldn't be possible without Mapbox and its Javascript web mapping module
  • While the maps were all made by me, it was all done with the help of the redistricting application Daves Redistricting
  • Some map visual changes, like clipping coastlines, were done with Mapshaper
  • Precinct data was collected from VEST
  • Probably dozens of other programs and Python/Javascript modules who I forgot about