PlanetMath

PlanetMath
Type of site
Online encyclopedia
Available inEnglish
OwnerPlanetMath.org, Ltd.
Created by
  • Nathan Egge
  • Aaron Krowne
URLplanetmath.org
CommercialNo
RegistrationGitHub account required to edit sources via pull request
Current statusInactive
Content license
CC BY-SA

PlanetMath is a free, collaborative, mathematics online encyclopedia. Intended to be comprehensive, the project is currently hosted by the University of Waterloo. The site is owned by a US-based nonprofit corporation, "PlanetMath.org, Ltd".

PlanetMath was started when the popular free online mathematics encyclopedia MathWorld was temporarily taken offline for 12 months by a court injunction as a result of the CRC Press lawsuit against the Wolfram Research company and its employee (and MathWorld's author) Eric Weisstein.