The Mayan Aztec calendar is calculated depending on the day you were born, the time you were born and the location in the world you were born. There are many Mayaonics Calendars available for download online, which is the simplest and most accurate way to calculate your Aztec birthday.
Download and install a Mayanonix calculator online and install on your desktop.
Open the calculator and fill in your full date of birth.
Look to the Tzolkin Day field which will list your Aztec birth date. The calculator will list your Tzolkin Tone and day sign.
If you were born two hours before or after midnight, this can change the Aztec Tone and sign. If you were born two hours before midnight, your true tone and sign may actually be the day before. Likewise if you were born within two hours after midnight, your tone and sign may be the day after. To clarify, study the traits of the tone and sign in the days surrounding the Aztec birthday to see if you more closely identify with another one.