http://www.hughcalc.org/chol.php
Enter any three of the following numbers and the calculator will find the fourth missing value, and then it will tell you the ratios and how good they are. You can read the article from the American Heart Association on desired levels here. The articles on the Total Cholesterol/HDL and HDL/LDL ratios from eMedTV can be found here and here, and the article on triglycerides over HDL ratio is here.
Enjoy!
Total Cholesterol
mg/dL
HDL (High density lipoprotein)
mg/dL
LDL (Low density lipoprotein)
mg/dL
Triglycerides
mg/dL