A useful bug report
Tell me whether you selected concentration or density, which units you chose, and what the calculator did. An invented example with the same issue is usually enough. Include the expected result and, for a layout problem, your browser and device.
Please do not send medical records, prescriptions, patient names, or other personal health details. If you attach a screenshot, remove identifying information first.
Support has a specific scope
I can look into the website and its arithmetic. I cannot recommend a medicine amount, interpret a prescription, or advise on treatment. A pharmacist or clinician is the right person to clarify medicine instructions or an uncertain label.
Use the same address for privacy or terms questions. The privacy policy explains how support emails are handled.