YEAR Function in ONLYOFFICE Spreadsheet Editor: Syntax, Examples and Date Checks

Extract the calendar year as an integer from an actual spreadsheet date or date-producing formula. In the English ONLYOFFICE YEAR reference, the exact published signature is =YEAR(serial_number). All displayed outputs below are independently calculated expectations, not results observed in an installed ONLYOFFICE editor.

YEAR extracts the year number from an underlying date value. In ONLYOFFICE’s official reference, the returned year is described as a number from 1900 through 9999. It does not retrieve the four digits from an arbitrary text string; use a genuine date produced by DATE or a verified date cell.

This is useful when grouping transactions into calendar years, checking whether a record belongs to a reporting cohort, and generating year boundaries. YEAR does not return an age or a duration: subtracting two year values can produce a misleading age when the anniversary has not yet happened.

=YEAR(serial_number)

The arguments above are required; the current official reference documents no optional parameters or default argument values for this function. In these formulas, parameter labels such as serial_number describe argument positions; you type a cell reference or numeric expression instead. English examples use commas. All values in the shared exercise are intended to represent unambiguous Gregorian calendar dates. YEAR vendor reference.

• ONLYOFFICE Docs / browser editor: vendor help confirms the documented function name and arguments, not reproducibility on every deployed server version. The Docs release history records version 9.4.0 (May 20, 2026), but does not establish that this function first appeared then.
• ONLYOFFICE Desktop Editors: desktop release history is separately maintained; Desktop 9.4.0 is dated May 19, 2026. Do not infer identical support, same error strings, or the introduction version from the shared product branding.
• Android, iOS and other integrations: this investigation does not establish native function support or evaluation parity for a specific app build. Open the function picker in the target editor and perform a local test.
• Formula language and locale: the Advanced Settings documentation describes separate Formula Language and Region controls, including date-display and separator settings. Formulas here use English names, = and commas. If the installed interface expects localized names or a different list separator, adapt and independently validate entry; date cells should be formatted explicitly rather than assumed to display the same across regions.
• 1900 vs. 1904 date system: the same Advanced Settings page documents an optional 1904 date system. It affects date serial calculations and imported workbooks. The tables below compare calendar dates, not hard-coded serial integers. Record the selected date system before comparing workbooks from another spreadsheet product.

Document checks: 2026-10-11 UTC. These are documentation findings, not test logs from a native ONLYOFFICE session.

Create a clean spreadsheet. Type the headings Year, Month, Day, Constructed date, YEAR result, MONTH result, DAY result into A1:G1. Enter the following numbers in A2:C9 (without quotation marks); never paste ambiguous date strings such as 03/04/2026 as input data. Place =DATE(A2,B2,C2) in D2 and fill down to D9. Set D2:D9 to a date format in which the calendar year, month and day are unambiguous—for example yyyy-mm-dd when available. If you see a large integer instead, the date display format probably needs adjusting.

For E2, enter =YEAR(D2); for F2, enter =MONTH(D2); for G2, enter =DAY(D2). Fill all three formulas down through row 9. The shared example-dates.csv in this batch contains the input numbers and independently expected values; the CSV is a test fixture, not an execution transcript. These expected outputs were checked using Python’s Gregorian datetime.date types, which do not simulate ONLYOFFICE’s formula engine or serial-date edge cases.

To reproduce the test without filling, enter each formula from the table below directly into its indicated output cell. Use the worksheet’s actual values, not screenshots or an imagined workbook.

Worked YEAR examples

Keep the shared D2:D9 dates and enter =YEAR(D2) in E2, filling down through E9. The table below isolates this function. All values are independently expected Gregorian years rather than observed ONLYOFFICE calculation outputs.

Advanced example 1: classify a record by its calendar-year cohort

Advanced example 2: create a year-start boundary without text parsing

Enter =DATE(YEAR(D4),1,1) in H5 and format as a date. Expected: 2026-01-01. This is useful for year-to-date filters and calendar-year reporting boundaries; it is not automatically the start of a non-January fiscal year.

Advanced example 3: check a full year span for an imported range

With D2 = 2024-02-29 and D9 = 2026-12-31, enter =YEAR(D9)-YEAR(D2) in H6. Expected: 2. This calculates a difference between year numbers, not the elapsed time in full years. It can support a simple reporting label but should not replace an anniversary/tenure calculation.

Practice diagnosis

If =YEAR(A4) gives a surprising value, remember that A4 contains the number 2026, not a complete date. Use D4, the constructed date, instead. This is one of the most common conceptual mistakes when working with date serials.

• Calendar year rather than worksheet label: cell formatting as dd-MMM-yy does not change the real year component; a user who sees 11-Oct-26 should still get 2026 in the expected Gregorian case.
• Time-of-day component: some date serials may contain a fractional time part; the official YEAR help does not detail every coercion case. Verify in the target editor before relying on fractional serials.
• 1900 boundary: the vendor documents returned years in the 1900–9999 range; this is not a complete specification of how every raw serial number is interpreted.
• YEAR versus YEARFRAC: YEAR gets a component of one date; YEARFRAC estimates the fraction of a year between dates using a day-count basis. Do not confuse them.
• YEAR versus DATEDIF: counting complete anniversaries needs a date-difference rule, not simply YEAR(end)-YEAR(start).

1. The date displays as an integer: ensure the output cell uses a date format. The date serial system is a separate setting from the on-screen formatting. Do not replace an integer with a text date and assume calculations will still work.
2. A formula shows as text: enter it with a leading =, avoid quoted formula strings, and confirm the cell is not forced to text formatting. Use the Insert Function picker to check the installed function name.
3. A copied formula gives unexpected values: compare each reference with the practice table; for example, D4 is the constructed 2026-10-11 date, while A4 is just the year 2026. A YEAR/MONTH/DAY function called on A4 would be interpreting a serial number, not reading the digits “2026” as a year.
4. Dates imported from another locale: 04/05/2026 is ambiguous without regional context. Prefer DATE(2026,5,4) or separately entered numeric parts for a reproducible check.
5. 1900/1904 mismatches: before trusting dates in a migrated Excel file, verify the workbook’s date-system settings. A function name matching in two apps does not prove equality of serial-number handling.
6. Invalid or blank inputs: the short official help pages do not document a complete error-code and type-coercion matrix. Test blanks, negative serials, strings, the year-1900 boundary and localized dates in the target installation; do not claim a specific #VALUE!/#NUM! result without observing it.
7. Unsupported edition or version: check the real product version, Formula Language, platform and installed function picker, then reduce the example to one literal DATE(...) and one extraction. A web documentation page is not a compatibility matrix.

Deliberately unresolved edge cases: the consequences of a day beyond the number of days in a month, month 0 or 13, years before 1900, decimal arguments, and non-Gregorian display calendars are not guaranteed by the short ONLYOFFICE references. The worked examples stay within documented argument ranges and valid Gregorian dates. Do not promote Excel’s normalization behaviour to a verified ONLYOFFICE rule.

Microsoft Excel documents corresponding DATE, YEAR, MONTH and DAY formulas, and Microsoft explains the use of sequential date serials. These are analogous English function names, not proof of matching outcomes for boundary dates, formula-language translations, cross-version imports, or 1900/1904 settings. Excel’s official date-function reference is a useful contrast; ONLYOFFICE Advanced Settings documents the date-system option inside this editor.

In particular, changing a date’s display format is not equivalent to changing the underlying date value. Do not use textual dates for cross-software validation. Export a small workbook and record the versions and chosen date systems in both products if interoperability is important. No comparative application execution was done during this research pass.

• DATE — official ONLYOFFICE reference (checked 2026-10-11 UTC).
• MONTH — official ONLYOFFICE reference (checked 2026-10-11 UTC).
• DAY — official ONLYOFFICE reference (checked 2026-10-11 UTC).
• YEARFRAC — official ONLYOFFICE reference (checked 2026-10-11 UTC).
• DATEDIF — official ONLYOFFICE reference (checked 2026-10-11 UTC).

• ONLYOFFICE Spreadsheet Editor — function documentation
• ONLYOFFICE Insert Functions index
• Docs release history
• Desktop 9.4.0 is dated May 19, 2026
• Advanced Settings documentation
• YEARFRAC
• DATE — official ONLYOFFICE reference

Verification status: Official documentation checked; example outcomes were independently reasoned or arithmetically checked where applicable. Not executed in ONLYOFFICE Spreadsheet Editor.

• No genuine ONLYOFFICE Spreadsheet Editor screenshots are included; this guide does not use mock application images.