ROT13 Function (Calligra Sheets)

• Introduced: First release not established; the name is present in Calligra 2.4.0 source.
• Supported in: Calligra Sheets 26.08.2, with the limitations described here; no retirement established.
• Scope: Desktop Sheets with the Text module. Formulas use English names and semicolon separators.
• Checked: October 14, 2026: selected 25.04.2 engine-library formulas and independent reconstructions; 26.08.2 source only. The test locale was C. No GUI-cell, import or other-locale execution is claimed.

ROT13 rotates the 26 ASCII letters by thirteen places and preserves ordinary ASCII letter case. It is useful for reversible spoilers or simple text puzzles. Anyone can reverse it by applying the same transformation, so it is not secure encryption and should not protect private data. Official function reference.

=ROT13(text)

text is the single required argument. Other value types pass through the value-to-string conversion before the character loop. The table shows the output strings exactly. Registration and implementation.

Quotation marks identify text results; error tokens without quotes are actual errors. Numeric results are rounded here to twelve decimal places. The reconstruction column applies independent decimal arithmetic or the inspected character/parser rules, rather than claiming another application test.

Enter Hello, World! in A2, then use =ROT13(A2) in B2. The result is Uryyb, Jbeyq!. Applying =ROT13(B2) restores the original ASCII text. Punctuation, spaces and digits in this example remain unchanged. This makes a convenient reversible display trick for a puzzle column, without introducing an encryption key or a security boundary.

For ASCII letters, positions A–M move forward thirteen and N–Z move backward thirteen. The same rule applies to lowercase ASCII letters, giving an involution: two applications recover the original input. The executed nested formula below checks that property for the greeting.

The general Unicode behavior is narrower. Long s ſ uppercases to ASCII S, causing thirteen to be subtracted from the original U+017F code point; the result is U+0172, Ų. Dotless i ı uppercases to ASCII I, causing thirteen to be added to U+0131 and yielding U+013E, ľ. These are source-explained observations, not the intended ASCII cipher. Restrict a reversible pipeline to validated ASCII text rather than assuming every Unicode string round-trips.

=ROT13(ROT13("Hello, World!"))

The executed result was "Hello, World!".

The listed accented Greek/Thai example and full-width Latin example remain unchanged, but that does not cancel the two specific Unicode exceptions. Behavior for all Unicode casing combinations was not enumerated.

Numeric input 123 becomes the string 123. TRUE is converted to lowercase true, then transformed to gehr. An error expression is also converted to text: 1/0 becomes the successful string #QVI/0! after rotation of #DIV/0!. Preserve and validate the original input if you need error propagation; the output can no longer be treated as the original error value. Wrong argument counts produced #VALUE!.

• Function-specific implementation
• Versioned help
• String Conversion
• Rot13 Alias

The complete selected callback is byte-identical in the inspected 25.04.2 and 26.08.2 sources. The text module has an unrelated SEARCH change; whole-file equality is not claimed. The locale helpers are byte-identical. These comparisons do not establish execution of the later release.

CODE, CHAR, LEN.