To convert "Earth" dates to Klingon dates, input the relevant date and time into the red cells to the left. Use military time for the "Hour" cell. The Klingon date will automatically generate, for that exact date and time, and also the start and end point of that "Earth" day. The calculator will also give you the Klingon date on which the majority of that "Earth" day falls. Changes will not be saved.

To convert Klingon dates to "Earth" dates, input the relevant date and time into the red cells to the right. Click on the Klingon "Month" cell to activate a drop down menu of all the Klingon months. Remember there are forty-eight days in a Klingon month, sixteen hours in a Klingon day, and forty-eight minutes in a Klingon hour. The Earth date will automatically generate, for that exact date and time, and also the start and end point of that Klingon day. The calculator will also give you the "Earth" date on which the majority of that Klingon day falls.

Rounding may give a one second difference when comparing the same date and time between the two different calculators.

Note that the calculator recognizes that the the calendar system changed from Julian to Gregorian in October 1582. Dates are given in the appropriate calendar version before and after that switch.

Changes will not be saved. Note, you are actually able to change the input of the non-red cells as well, but again, changes will not be saved. You may have to allow third-party cookies for the calculator to load.