The Columbia-Suicide Severity Rating Scale (C-SSRS), the most evidence-supported tool of its kind, is a simple series of questions that anyone can use anywhere in the world to help prevent suicide.
This is the American Legion sponsored version of the Columbia Protocol app that is geared more towards veterans.
Disclaimer: If you are high risk, a further evaluation is indicated. For Low or Moderate answers, a mental health referral may be helpful or is provided.