Free tools
Count days between two check-in dates
Enter two dates to count calendar days between them. This calculation does not measure someone’s wellbeing or explain a missing update.
Your entries stay in this page. Nothing is sent or saved by this tool.
The counting convention
The result counts date boundaries. October 1 to October 2 is one day. The same date is zero days. Enable inclusive counting to count both dates.
Worked example
February 28 to March 1, 2024 is two days because February 29 exists that year. The same dates in 2025 are one day apart.
Keep the dates consistent
Use dates from the same time convention, preferably the sender’s local dates. The tool works with calendar dates in UTC for arithmetic and ignores hours and daylight saving.
Limits
The end date must not precede the start date. Use years from 1900 through 2100. The result has no connection to the app’s records, history, or alerts.
Keep your daily check-in in DailyCheck
A private update on your iPhone, shared only with your chosen people.
Get DailyCheck freeFree for you and up to four people.
iPhone · iOS 26 or later · iCloud required