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 (2020), MJA (2020), and PLOS ONE (2021) evaluated online symptom checkers for condition coverage, diagnostic accuracy, and appropriateness of urgent care advice. We used these studies 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
    Incredibly well designed and accurate symptom checker. Diagnostic accuracy of 77%. - Registration Required, App Only
  • Buoy
    Buoy is an AI-powered chat-based symptom checker. Diagnostic accuracy of 52%.
  • Isabel
    Relied upon by doctors and nurses around the world. Diagnostic accuracy of 68%.
  • Symptomate
    Powered by Infermedica. Expect many branched logic follow-up questions. Diagnostic accuracy of 60%.
  • WebMD Symptom Checker
    Most popular online symptom checker with interactive body map. Diagnostic accuracty of 59%.

Additional Tools

    Easy to use symptom drill down tool powered by Harvard Medical School.
  • Family Doctor
    Easy to use, fairly basic symptom checker.
  • Healthily (by
    Self-care health app. Includes conversation-themed symptom checker.
  • Healthline: Symptom Browser
    Browse condition and treatment articles by symptoms.
  • K Health
    Question-based symptom checker. Unfortunately, registration is required. - Registration Required, App Only
  • Mayo Clinic
    Choose your primary symptom and related factors to narrow potential medical conditions.
  • Mediktor
    Web-only, AI-based medical assistant for triage and pre-diagnosis. Based in Spain.
  • ShareCare: AskMD
    Be prepared to share a lot of personal health information. - Registration Required
  • Skinsight
    High quality dermatology information site offering a rash and skin condition identifier tool.
  • SymCAT
    Probability-based diagnostic tool that factors in patient history.