DURATION Function in Apple Numbers: Syntax, Examples and Troubleshooting

• Introduced: Documented in Apple’s Formulas and Functions Help 15.4; the original introduction release is not established.
• Availability: Supported by the current Apple Formulas and Functions Help 15.4 documentation for Numbers; no final supported-version endpoint is identified.
• Scope: Shared iWork function reference; the formatting steps below refer to Numbers for Mac. Older releases and individual-client introduction dates are not established here.
• Checked: October 14, 2026, against the official DURATION reference. Documentation and independent arithmetic checks; no native Numbers test.

=DURATION(weeks, days, hours, minutes, seconds, milliseconds)

Every component accepts a number. Each position is optional, but at least one numeric argument must be supplied. An omitted component contributes zero. If a later component is present, keep the separators for earlier omitted positions; trailing unused arguments can be left out. These rules, and support for negative components, are stated in the official reference.

For example, =DURATION(0,0,2,15) and =DURATION(,,2,15) both describe two hours fifteen minutes. =DURATION(2,15) describes two weeks and fifteen days instead: deleting argument positions changes the units. Explicit zeros make formulas easier to inspect.

Create a table with at least eight columns and seven rows. Use these headers in A1:H1: Weeks, Days, Hours, Minutes, Seconds, Milliseconds, Duration, Total seconds. Type the numeric components below into A2:F7.

In G2, enter =DURATION(A2,B2,C2,D2,E2,F2) and fill through G7. In H2, enter =DUR2SECONDS(G2) and fill through H7. Format G2:G7 as Duration and H2:H7 as Number. DUR2SECONDS makes the total visible without relying on one particular duration display style.

The normalization is arithmetic: the 90 minutes in row 4 are still ninety minutes even if the cell displays an hour and thirty minutes. In row 6, two days minus 24 hours leaves one day. None of these examples selects a month, year, time zone or holiday calendar.

Use a separate table named Adjustment with at least five rows and columns A:D. Put Base hours in A1, Extra minutes in B1, Adjustment hours in C1 and Revised duration in D1. In row 2, enter 8, 45 and -2 in A2:C2.

In D2, enter:

=DURATION(0,0,A2+C2,B2)

The expected duration is 6 hours 45 minutes: eight planned hours plus 45 extra minutes minus two hours. For a decimal-hours output, place =DUR2HOURS(D2) in D3; expect 6.75. This keeps the adjustment numeric and in its proper unit instead of concatenating a text label such as 6.75h.

A fractional week is also valid: put =DURATION(0.5) in D4, and =DUR2HOURS(D4) in D5. The duration is three days twelve hours, equivalent to 84 hours. For work schedules, use your actual hours-per-workweek definition separately; a duration week is seven full days.

On Mac, select the duration cells and choose Format > Cell > Data Format > Duration. Use Automatic Units or Custom Units to choose the displayed span. Apple’s formatting help explains that hiding smaller units does not remove their contribution to later formulas.

• No components: DURATION() does not meet the documented requirement for at least one argument. Use DURATION(0) when zero elapsed time is intended.
• Wrong units: a value in the first position is weeks, even if you intended hours. Prefer explicit zeros or cell references under clearly labeled headers.
• Text components: the documented input type is numeric. Clean imported text first; this guide does not assume all strings are silently coerced.
• Calendar or clock task: use TIME for a time of day. DURATION creates an interval and cannot by itself identify a calendar deadline.
• Rounding: changing a cell’s displayed units is different from applying a business rounding rule. Convert to the appropriate numeric unit before using ROUND.

Apple’s page does not specify a complete error-code table or all precision limits. Its displayed millisecond examples do not establish a universal truncation rule.