Your own interval, turned into a due date
Enter the date you last rotated or flipped the mattress and the interval in whole months you have decided to follow. The page returns the next due date, the time left from your reference date, how many scheduled dates have already gone by, how many times a year the interval comes around, and which task is next if you alternate rotating and flipping. Whether the number of missed dates is odd or even decides that task.
The interval is yours to set
No published, authoritative interval for rotating or flipping a mattress is offered here. The figures that circulate are common practice rather than a standard, and one-sided mattresses are built never to be flipped at all. That is why the interval is an input instead of a default. Copy the figure from your product manual or the maker's care sheet. Current as of October 2026.
Limits and disclaimer
Dates are built from year, month and day components, and a day number the target month does not have is pulled back to the last day of that month. This page does not assess the condition of a mattress and does not tell you when to replace one; it only counts dates and repetitions. Follow your product manual and the manufacturer's instructions first.
Frequently Asked Questions
No authoritative interval is offered here. The numbers that circulate widely are common practice rather than a published standard, and some mattresses are built never to be flipped. Take the interval from your product manual and enter it as an input.
Rotating swaps the head end for the foot end so you lie on a different part of the surface. Flipping turns the whole mattress over onto its other face. A one-sided mattress cannot be flipped, so choose rotating only in that case.
If the target month has no matching day number, the date is pulled back to the last day of that month. January 31 with a one-month interval lands on February 28, or February 29 in a leap year.