Covid Test Calculator

Not at all: You take no special Covid precautions and live life as if the pandemic is over.
Slightly: You take only minor precautions occasionally—masking or testing in special situations—but mostly live as if the pandemic is over.
Moderately: You regularly employ some Covid precautions (like masking indoors and testing) while still engaging in most social and work activities.
Very: You maintain extensive Covid safety measures at all times—such as always wearing a high-quality mask and avoiding most indoor exposures—significantly altering your daily life.
Extremely: You adopt a near-zero risk tolerance for Covid, living in semi-isolation with maximal precautions—e.g., respirator-level masking and minimal in-person interaction—to completely minimize your exposure.

Do you have symptoms?

How Covid-cautious are you?

Test Type: Test Result:

Local Covid Prevalence (%) (optional)
See, for example, the PMC's current regional estimates (bottom right of second image).

Local Positivity Rate (%) (optional)
See, for example, the Walgreens Respiratory Index for current state-by-state positivity rates.

Prior Probability of Infection (%) (optional)
If provided, then the probability of infection is determined solely by this value and your test result(s).