Help and answers
Frequently asked questions
Quick answers on how leap days, month lengths, and date intervals are counted, plus how to use each calculator with confidence.
Common questions
How are leap years handled?
Calculations use the Gregorian calendar, so February 29 is counted in leap years and months use their actual day lengths.
Why do weeks and months give different results?
Weeks are fixed at seven days, while months vary between 28 and 31 days, so the same span can show different totals by unit.
What do the input checks cover?
Each calculator checks that dates are complete, valid, and in a logical order before showing a result, with a message when something needs correcting.
Are retirement results guaranteed?
The Retirement Calculator provides an estimate based on the ages you enter. It does not offer financial advice or guaranteed outcomes.
Do time zones change a result?
Calculators work with calendar dates only, so time zones and clock times are not used in the count.
Is my date information stored?
Calculations run in your browser. Review the Privacy Policy for details on how the site handles data and cookies.
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