ASC in Collabora Office Calc: Normalize Fullwidth Codes and Katakana

=ASC(Text)

Text is the string, or a reference to the cell containing it. The result is text, not a character code. The formulas use English function names and semicolon argument separators. Adapt these to your formula settings; do not type square brackets used to mark optional arguments. Put input data in a source column and formulas in a separate result column so you can inspect both.

Enter the source values in A2:A4. In B2 enter =ASC(A2) and fill down.

The fullwidth letters, hyphen and digits convert. The existing Latin letters remain intact. The kanji in the third row are preserved: this is width conversion, not translation or transliteration of Japanese words into Latin letters.

=ASC("カナ１２") is expected to return ｶﾅ12. The two katakana become their halfwidth forms, and the fullwidth digits become ordinary digits. =ASC("Desk-12") returns Desk-12, while =ASC("") returns the empty string.

These examples use unvoiced katakana deliberately. Voicing marks and punctuation can require special conversion rules; use the official conversion table when you need an exact mapping for those characters. Do not substitute a generic Unicode normalization routine and assume it implements ASC.

Suppose A2 contains ＡＢ－１２ and D2 contains AB-12. Put =ASC(A2) in B2 and =EXACT(B2;D2) in C2. The expected results are AB-12 and TRUE. Keep A2 as the original audit value, and use B2 as a normalized key only after checking that the downstream system accepts that representation.

ASC does not remove leading spaces, change letter case, or validate the structure of an identifier. For example, =ASC("Ａb") returns Ab, so a case-sensitive comparison against AB remains false. An identifier containing leading zeros should be stored as text before import; width conversion cannot restore zeros already lost through numeric conversion.

• Single-width ASCII remains unchanged. An unexpected unchanged kanji is not a failure: only supported width variants are converted.
• A numeric input may be converted to a textual representation. For reproducible identifiers, pass text rather than depending on a number format or locale-specific number conversion.
• The input must be a string expression or a valid cell reference. Quote literal text; an unquoted word can be interpreted as a name.
• Existing input errors propagate. Check the source cell before wrapping a larger import formula in an error handler.
• Missing or extra arguments are formula errors; ASC takes one argument.

The implementation calls the dedicated FULLWIDTH_HALFWIDTH_LIKE_ASC transliterator. It is not an instruction to encode the result into an ASCII file: halfwidth katakana are still Unicode characters, and non-ASCII text can remain in the output. In particular, Collabora’s B-functions count the Halfwidth and Fullwidth Forms block with weight two. Do not promise that ASC will reduce LENB for every katakana string. Pinned ASC implementation.

For related work, use LEFT for prefixes and LEN for ordinary text length. Consult the vendor-linked conversion table for detailed mappings.

Documented in a Collabora Office 26.04 Help snapshot retrieved October 17, 2026, from the linked latest Help pages, and reviewed October 19, 2026, against the Collabora co-26.04 source commit linked below. Fresh retrieval attempts for the versioned 26.04 Help pages returned HTTP 503, so the documentation evidence is the saved snapshot rather than a successful fresh retrieval. The first release that introduced the function is not established here. Online, mobile and later desktop deployments may differ; confirm function availability and settings in the actual client.

Checked October 19, 2026. The expected answers were independently calculated from documented rules and the pinned implementation. These are not results captured from a running Collabora application; native execution and screenshots were unavailable. No screenshot is presented as evidence.

• Collabora Office ASC Help (26.04 snapshot, retrieved October 17, 2026)
• Pinned Collabora implementation