Plan with dates

Find shared days, group dates by how long ago they were, and understand a fiscal year. All dates stay on this device.

When do two date ranges overlap?

Both the start and end dates count. If one range ends when the other starts, they share one day.

How old are these dates?

Group up to 500 dates by elapsed calendar days. A date matching the reference date is 0 days old. Future dates have their own group.

Which fiscal period is this?

This uses twelve calendar months and four three-month quarters. Choose your organization’s start month and year naming rule. It does not model retail 4–4–5 calendars.

Date

Fiscal year starts in

Name the fiscal year after its

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Need to skip weekends or your own holidays? Use business dates.

EXAMPLES & HELP

Examples for date ranges, aging and fiscal years

These planning tools answer three different questions: when two schedules overlap, how many calendar days old a list of dates is, and which fiscal period a date belongs to. Each calculation uses dates rather than time-of-day cut-offs.

How to use this calculator

Choose the section that matches your question: shared dates, age groups or fiscal periods.
Enter the date ranges, date list or fiscal year start month. Aging lists use YYYY-MM-DD, one date per line.
Calculate and inspect the boundaries. Fiscal results can also be downloaded as a CSV calendar.

Worked examples

Two ranges meet on the same date

Start with: First range: 1–29 February 2024. Second range: 29 February–1 March 2024.
Result: 1 shared day: Thursday, 29 February 2024.

Both ranges include their start and end dates. February 29 belongs to both, so meeting on an endpoint is a one-day overlap rather than zero.

A fiscal year beginning in April

Start with: Date: 29 February 2024. Start month: April. Name year after: End year.
Result: FY 2024, quarter 4, period 11.

This year runs from 1 April 2023 through 31 March 2024. February is its eleventh month and lies in its fourth quarter. Naming by the start year would label the same period FY 2023.

Dates on either side of an aging boundary

Start with: Reference: 1 March 2024. Dates: 31 January and 30 January 2024.
Result: 30 days old → 0–30 days; 31 days old → 31–60 days.

The first group includes both 0 and 30 days. The next begins at 31. A reference-day item is zero days old; dates after the reference date go into the Future group.

Common questions

Does fiscal year mean January to December?

Only when January is selected. The chosen start month defines twelve calendar-month periods, grouped into four quarters. This tool does not model retail 4–4–5 or 52/53-week calendars.

Are aging buckets based on business days?

No. They use elapsed calendar days, including weekends and February 29. Duplicate input dates remain separate rows and each contributes to its group’s count.