ISERR Function (Gnumeric)

Use ISERR to detect an error other than #N/A. This is useful when a missing lookup result should be handled differently from a broken calculation. In Gnumeric’s Information manual, ISERR explicitly excludes #N/A while ISERROR includes it. R1

=ISERR(value)

value (required) is a cell reference or evaluated expression. It may be an error, a successful number, text, or a logical value. The only return states documented for the predicate are the logical values TRUE (an error except #N/A) and FALSE (otherwise). There are no additional parameters. R1

Native-validation limits: Examples are documentation/source-based expectations, not observed Gnumeric execution or screenshots.

Version and platform: The official Gnumeric manual is labelled 1.12 and documents this Information-category function. The project announced Gnumeric 1.12.62 in the current 1.12 series. The official public catalogue lists this function as Complete with Basic project testing, which is not a claim that any examples in this guide were executed. Core Information functions are documented in Gnumeric; actual availability still depends on the reader’s installed version and environment. The introduction date in an earlier minor release was not established. R1R6

Formula notation / locales: Use a leading = in a cell; the examples use the manual’s English function names. This function requires exactly one argument and has no optional parameters or documented defaults, so there is no argument-separator ambiguity in its own syntax. In nested expressions the official formula documentation illustrates commas; operating-system locale can affect language and numeric formats, so check your Gnumeric installation if a pasted multi-argument formula is parsed differently. R4

1. Open a new worksheet. Add descriptions in A2:A6 if helpful.
2. Enter the exact =... formulas in B2:B6 shown below; do not type the displayed error labels manually.
3. Enter the matching test formulas in C2:C6. The results below are expected, not native observed.
4. Compare your installed Gnumeric results and record the local version, locale, and mismatches before adoption.

On a narrow screen, scroll sideways to view this complete example.

Reading the results: Do not treat a #N/A display as a non-NA error; distinguish text from real spreadsheet error values. The classification follows the official definitions R1 and Gnumeric’s documented error/cell types R4.

Triage a calculation report without hiding missing records

With the values in B2:B6 above, enter this in D2 and fill down:

=IF(ISNA(B2),"Not supplied",IF(ISERR(B2),"Investigate formula",B2))

Expected: D2 = 4; D3 = Investigate formula; D4 = Not supplied; D5 = the literal text #N/A; D6 = Investigate formula. The outer IF intercepts only actual #N/A, whereas the inner ISERR checks other failures. Gnumeric’s IF documentation states that only the selected branch is evaluated. R1

Count non-#N/A failures in a short audit column

Place =ISERR(B2) through =ISERR(B6) in C2:C6 as shown in the example. A separate =COUNTIF(C2:C6,TRUE()) is expected to count 2 true flags; this counting expression is an independently reasoned combination and needs native confirmation before use in a regulated workbook. For a large report, build the helper column once and filter it rather than replacing error cells with misleading zeros.

• Why is NA() FALSE? It produces the real missing-value error #N/A, which the official ISERR definition deliberately excludes. To flag it, use ISNA or ISERROR. R1
• Why is a displayed "#N/A" FALSE? Entering quoted text creates text, not an error. To reproduce an actual missing-value error, use =NA(); do not type or paste an error-looking label. R1
• Why does an underlying formula still fail? ISERR diagnoses; it does not repair division-by-zero, invalid references, or domain errors. Inspect source inputs before applying an IF wrapper. R4
• Why does a formula show #NAME?? Check ISERR spelling, the leading =, and that the expected built-in function is available in the installed release; Gnumeric lists unrecognized names as a source of #NAME?. R3
• Why do nested commas fail? Gnumeric’s English documentation separates function arguments with commas, but locale settings may differ on an installed system. Check the application’s parser/settings, not the ISERR argument count. R4

The official Gnumeric manual explicitly describes ISERR as Excel compatible. That is a documented compatibility claim, not evidence of testing every Excel edition or third-party spreadsheet. The exact distinction between ISERR, ISNA and ISERROR matters more than a general portability assumption. R1 The public catalogue reports a Complete implementation and Basic project testing for this canonical spelling; this is metadata about the project, not a site-specific validation record. R3

ISNA · ISERROR · NA · IF · IFERROR · IFNA.

The official Gnumeric 1.12.62 source archive was checksum-verified; the Information-function callback confirms the documented error classification without requiring inference from another spreadsheet.

The following are official Gnumeric references (accessed 2026-10-12 UTC), not evidence of live testing:

• R1 Information-function manual, Gnumeric 1.12: Official synopsis, argument and behaviour.
• R2 Logic-function manual, Gnumeric 1.12: IF, IFNA and IFERROR selection semantics.
• R3 Gnumeric function catalogue: Implementation/testing classifications.
• R4 Gnumeric formulas and cell types: Formula entry and error values.
• R5 Languages and locales: Operating-system locale configuration.
• R6 Version 1.12.62 announcement: Official release announcement.
• R7 Official source archive: 1.12-series downloads.

Validation: Official documentation and checksum-verified Gnumeric 1.12.62 source were inspected; displayed logical outcomes were independently reasoned. Native Gnumeric execution, screenshots, locale regression and workbook round-trip tests were not performed.