REGEXTEST Function in Gnumeric: Syntax, Examples and Troubleshooting

=REGEXTEST(text, pattern, [case_insensitive])

The TRUE setting changes matching case, not the underlying string. The source compiles the regex with a case-insensitive flag only when this argument is true; invalid regex syntax returns a #VALUE!-type formula error. This is a search, not a data validator unless you use ^...$.

1. In A1 type Input code; in B1 type Strict match; in C1 type Ignore case.
2. Enter the following literal values in A2:A6.
3. In B2 enter =REGEXTEST(A2,"^ID-[0-9]{3}$"); fill B2:B6.
4. In C2 enter =REGEXTEST(A2,"^id-[0-9]{3}$",TRUE); fill C2:C6.
5. Check each expected Boolean below; these are independently calculated, not observed application results.

Why: The strict pattern requires uppercase ID, a hyphen, and exactly three digits with nothing before or after. In C, TRUE allows lowercase id, so row 3 passes.

For A2=Order ID-123 archived:

=REGEXTEST(A2,"ID-[0-9]{3}")

Expected: TRUE, because the text contains ID-123. The anchored form =REGEXTEST(A2,"^ID-[0-9]{3}$") is expected to be FALSE because extra words occur around the code. Use full-cell validation for importing fixed-format identifiers; use unanchored search to find an embedded code in notes.

To make the expression reusable, put the pattern ^ID-[0-9]{3}$ as literal text in D1 and enter =REGEXTEST(A2,$D$1). The result for A2=ID-123 is TRUE; $D$1 keeps the pattern reference fixed as you fill down.

• Everything matches unexpectedly: A pattern such as ID finds a substring. Add ^ and $ to require the whole cell to match.
• Case differences: With omitted third argument, id-123 does not match ^ID-[0-9]{3}$. Use TRUE when desired, and review for unintended matches.
• Literal punctuation: . means any character in most regex syntax. To match a literal period safely without a backslash, use [.].
• Invalid pattern ([0-9): The inspected Gnumeric source returns a #VALUE!-type error for a regex compile failure. The exact translated/error display has not been native-tested.
• Nontext identifiers or leading zeros: Keep codes stored as text; converting 007 to numeric 7 destroys the original string shape.
• Import/application mismatch: Regex engines differ; validate complex lookarounds, Unicode character classes and locale-specific rules in the target release rather than assuming an Excel/Google Sheets pattern transfers unchanged.

Excel for Microsoft 365 documents a REGEXTEST function using case_sensitivity, where 1 means case-insensitive; its documented engine is PCRE2. Gnumeric’s third argument is a Boolean named case_insensitive. This tutorial does not certify identical behavior for all advanced regex features or Excel versions. Other tools may use REGEXMATCH or different names/engines.

These examples target Gnumeric 1.12.62, whose official release announcement lists this function as newly introduced. Its registered name and argument information were checked against the GNOME source-code function definitions and string-function registry (GitHub’s GNOME mirror, pinned to commit 5d556a736fa3). The project’s release-specific source archive was enumerated in the pre-existing independent catalogue audit, but its bytes were not downloaded again in this batch. The public Gnumeric function index lags the audited release registry; absence from that list does not prove absence from 1.12.62. This guide does not promise availability in earlier versions or every downstream installation with different plugins.

Formulas use an English-language, comma-separated argument style with decimal dots where necessary. Regional settings can change the displayed argument separator and translated user interface; if pasting fails, insert the function through Gnumeric’s own function editor. Regex patterns are strings, so put double quotes around literal patterns in a formula; cell references such as A2 do not take quotes. A regex searches for a match within a string unless you explicitly anchor it with ^ and $. The implementation calls GLib GRegex; pattern portability with other spreadsheet regex engines is not guaranteed.

• Gnumeric — function documentation
• GNOME source-code function definitions
• string-function registry
• Gnumeric function index

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

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