MDETERM Function in ONLYOFFICE Spreadsheet Editor: Find a Matrix Determinant

=MDETERM(array)

No argument is optional, and there is no implied default. Source matrix entries should be numeric, including zero where intended; leaving a cell blank is not equivalent to zero in vendor-documented error handling. Preserve the order of arguments when combining matrix functions.

Vendor-confirmed errors: ONLYOFFICE explicitly documents #N/A when a referenced matrix contains empty or non-numeric cells, and #VALUE! for a non-square range. A numerically singular but correctly shaped matrix is not the same as a malformed range: its mathematical determinant is zero; this expected zero is not a native error-handling test.

Start with a blank worksheet. Type each entry as a numeric cell (not as quoted text), then place results only in the indicated unused output cells. The sample is deliberately small enough for manual checking.

Select a blank output area before entering each formula. Never overwrite these input ranges with array-formula results. Use one clean worksheet per guide, or reset your worksheet to this exact baseline before moving between scenarios.

Each displayed matrix is written as rows inside [[...],[...]]. For example [[2,-1],[-3,2]] means output row one 2, -1 and output row two -3, 2; it is not a formula literal to paste into the spreadsheet. Fill the indicated output rectangle using the actual formula, not by typing the expected array. These predictions were calculated with exact rational SymPy mathematics and do not represent measurements from ONLYOFFICE.

For a small 2×2 matrix [[a,b],[c,d]], calculate ad−bc by hand and compare the result to MDETERM. To check invertibility, use =MDETERM(A2:B3) and inspect whether its result is far from zero relative to the scale of your data. Do not classify a floating-point result merely by =0 when conditioning is poor: an ill-conditioned matrix may have a tiny nonzero determinant even when inversion is numerically unreliable. As another matrix identity, det(AB)=det(A)det(B) can be tested with =MDETERM(A2:B3)*MDETERM(D2:E3) and, separately, =MDETERM(MMULT(A2:B3,D2:E3)) as an advanced editor test, not a claimed observed result. The independent expectation for both sides with our dataset is −3.

• MINVERSE — related matrix operation, with its own documented signature and error conditions.
• MMULT — related matrix operation, with its own documented signature and error conditions.
• MUNIT — related matrix operation, with its own documented signature and error conditions.
• Function entry and argument-picker instructions.
• Array formula entry and array editing.
• Formula language and regional settings.

This guide is based on the current, unversioned English ONLYOFFICE help pages on 2026-10-13 (UTC) and independent numerical reasoning. The sample values below are expected values, not results observed in a running ONLYOFFICE Spreadsheet Editor. No screenshot, workbook execution, web edition test, Desktop edition test, or historic version support test was performed. Use the official function catalogue.

Edition and compatibility: ONLYOFFICE’s documentation describes the current Docs Spreadsheet Editor; its Desktop changelog and Docs changelog are distinct records. None of the cited function pages establishes a first-supported Desktop or web version for this function; do not infer universal historical compatibility or claim that an XLSX exported to another spreadsheet program evaluates identically. Where a function returns an array, the current ONLYOFFICE array-entry guide explicitly describes selecting the complete output range, entering the formula and pressing Ctrl+Shift+Enter. Do not manually type the surrounding { }. In some editions, dynamic-array behaviour may differ and must be tested.

Formula language and separators: The examples use English names, A1-style references, a decimal point, and commas between arguments. The official function-entry guide shows these conventions. The Advanced Settings guide documents configurable formula language, region and numeric separators; it does not provide a verified translation or formula argument separator for every locale. Change regional settings as appropriate and verify the resulting formula entry in the target edition rather than blindly substituting commas with semicolons.