In Finland, it is possible to quickly produce medical symptom self-assessment tools within the existing infrastructure. The Finnish Omaolo Covid-19 web-based symptom self-assessment tool (symptom checker) was launched on March 16, 2020 after a 6-day development period. By using the web-based Omaolo Covid-19 symptom checker during the second wave of the epidemic, some 1.72 million questionnaires were recorded, out of which 1.55 million from symptomatic persons. Some 15% of the responses (245,500) were directed to seek emergency medical care based on the online screening by respondent response profiles.