Use this calculator to convert between formats for time-keeping accuracy measurements and to determine the crystal frequency error as a function of the temperature response of the crystal.
Enter Operating Temperature  °C
Enter Deviation (enter only one, the other two will be calculated):

or  Seconds/Day

or  Minutes/Year

Temperature-Dependent Calculations:
  Crystal Frequency Error    PPM    sec/day    
  DS3231, DS3232, DS3234 Accuracy ± PPM    

Enter desired operating temperature. Enter desired deviation in ppm, sec/day, OR min/yr. Click the 'calculate' button next to your entry to calculate the corresponding accuracy and error measurements.
Note: Temperature dependent crystal frequency error in ppm is determined using the formula:
Error (ppm) = -0.042(25 - OperTemp)²
Also see: DS3231 I²C RTC