How parenting time is calculated
Parenting-time percentage is usually calculated the same way family courts and child-support guidelines do it: count overnights, divide by the number of nights in the period, and multiply by 100. Over a full year that's (overnights ÷ 365) × 100. This calculator does the same math over a 14-day cycle, since most custody rotations repeat on a two-week basis, then projects it across a year.
This tool is for planning and conversation, not legal advice — if a percentage matters for child support or a court filing, confirm the calculation method your jurisdiction uses with your attorney.
Common splits and what they look like
A quick reference for the overnight counts behind frequently cited splits, out of a 14-night cycle:
| Split | Nights / 14 | ≈ Nights / year | Typical pattern |
|---|---|---|---|
| 50 / 50 | 7 / 7 | 183 / 183 | Week-on/week-off, 2-2-3, 2-2-5-5, 3-4-4-3 |
| 64 / 36 | 9 / 5 | 235 / 130 | Extended-weekend variations |
| 79 / 21 | 11 / 3 | 287 / 78 | Every other weekend |
| 93 / 7 | 13 / 1 | 339 / 26 | Every other weekend, no extra visits |
FAQ
Is this the same formula courts use?
Most U.S. jurisdictions calculate parenting time as a share of overnights, which is what this tool does. Some states use different rules (daytime-only visits, or a parent's "available" time rather than overnights). Ellsby isn't a legal tool — check your state's child-support guidelines or ask your attorney if the number needs to be precise for a filing.
Why 14 nights instead of 7?
Most real custody rotations (2-2-3, 2-2-5-5, 3-4-4-3) don't repeat weekly — they repeat every two weeks. Counting over 14 nights gives an exact, whole-number split for all of them; a 7-night week would round several of these patterns incorrectly.
Does this account for holidays or vacation weeks?
No — it assumes the regular rotation repeats all year. Holiday schedules and vacation time usually shift a few nights either way; for an exact annual count including those, you'd adjust manually or track actual nights in Ellsby.