Symptom Checkers

Symptom checkers provide individuals with a fast way to identify possible causes for their medical symptoms. Users enter their symptoms and respond to targeted follow-up questions that help narrow the possible causes. Studies published in the British Medical Journal (2015) and MJA (2020) evaluated online symptom checkers for diagnostic accuracy. We used these studies and additional research to assemble this list of the best free symptom checkers on the web. Diagnostic accuracy represents the percentage of result sets that yielded a correct diagnosis among the top three results (averaged across studies).

  • Ada
    Well designed and easy-to-use question-based symptom checker. - Registration Required, App Only
  • Isabel
    Relied upon by doctors and nurses around the world. Diagnostic accuracy of 66%.
  • ShareCare: AskMD
    Highly rated at 68% accuracy but be prepared to share a lot of personal health information. - Registration Required
  • SymCAT
    Probability-based diagnostic tool that factors in patient history. Diagnosis with 60% accuracy.
  • Symptomate
    Powered by Infermedica. Expect many branched logic follow-up questions. - Also found on Everyday Health
  • WebMD Symptom Checker
    Most popular online symptom checker. Select symptoms using search or an interactive body map.

Additional Tools

  • Buoy
    Launched in 2017, Buoy is an AI-powered chat-based symptom checker.
    Easy to use symptom drill down tool powered by Harvard Medical School.
  • Family Doctor
    Easy to use symptom checker that provided a 51% diagnostic accuracy score.
  • Healthily (by
    Self-care health app. Includes conversation-themed symptom checker.
  • Healthline: Symptom Browser
    Browse condition and treatment articles by symptoms.
  • Mayo Clinic
    Choose your primary symptom and related factors to narrow potential medical conditions.
  • Skinsight
    High quality dermatology information site offering a rash and skin condition identifier tool.