If you were standing on another planet it would most likely have a different numerical day and year. To understand how relative time works on other planets it would be easiest to view this on a scale, where 1 is the slowest spinning and orbiting planet and 100 is the fastest spinning and orbiting planet. If we then started to enter all known planets and data we would eventually have a resource to be able to effectively estimate the relative planetary time of new planets discovered.
To estimate the rotational period or day of a planet in a different solar system you first need to convert the estimated need to convert the numer of days into seconds, then using Kepler's Formula: 4(Pi)^2 * A^3 / G * P^2
Try to estimate the mass of the star
Then find an accuracy ratio by dividing the result by the actual mass of the star, to find the time difference results. If the result is greater than 1.5 * 24. If the result is less then divide 24/result.
By doing this you can find out how many seconds the day length of a target planet is different than earth's day length, by determining the difference of the mass results in the equation and using the accuracy difference to adjust the seconds result.
