CEILING.MATH in Collabora Office: Round Up with a Sign-Independent Step

• Introduced: original Collabora release and launch date are not established by the sources reviewed.
• Availability: documented in Collabora Office 26.04 help, scoped to the desktop-help release.
• Platform scope: support in every online or mobile deployment is not inferred from desktop documentation.
• Checked: October 14, 2026. Complete function-specific documentation and independent arithmetic controls; no native Collabora test was performed.

=CEILING.MATH(number[;significance[;mode]])

Optional significance defaults to 1. Its sign is ignored. Positive inputs round away from zero. Negative inputs round toward zero when mode is omitted or zero, and away from zero when mode is nonzero.

This sign-independent rule differs from CEILING, whose opposite-sign arguments produce an error. The examples use English function names and semicolon separators.

Enter 21, 23, 25 and 26 in A2:A5:

=CEILING.MATH(A2;5)
=CEILING.MATH(A2;-5)

Both columns are expected to return 25, 25, 25 and 30. The step sign does not select a rounding direction. An exact multiple remains unchanged.

This can be useful when an imported configuration contains a signed step, but the surrounding model should still require a meaningful, nonzero spacing.

=CEILING.MATH(-23;5)
=CEILING.MATH(-23;-5;0)
=CEILING.MATH(-23;5;1)

Expected results are -20, -20 and -25. The first two move toward zero. The third moves away from zero.

For an additional nonzero-mode control, =CEILING.MATH(-23;5;-2) is also expected to return -25. Mode -2 does not mean “move two steps”; the documented distinction is zero versus nonzero.

Suppose planned headcounts are 21, 25 and 26, and a room configuration is available only in groups of five places. Fill down:

=CEILING.MATH(D2;5)
=CEILING.MATH(D2;5)-D2

Expected capacities are 25, 25 and 30; spare places are 4, 0 and 4. Summed capacity is 80, compared with 72 people.

If all three groups can share one combined space, =CEILING.MATH(21+25+26;5) gives 75, leaving three spare places. That alternative changes the grouping assumption, not the function’s arithmetic.

For inputs -11, -10 and -9, a step of five and mode zero give -10, -10 and -5. Mode one gives -15, -10 and -10.

Put the original, mode-zero result and mode-one result in adjacent columns. This makes the unchanged exact multiple and the two different signed policies easy to inspect.

Neither rule is nearest-multiple rounding. For example, the default result for -9 is -5 even though -10 is closer. MROUND addresses a different rounding objective.

The dedicated Collabora reference describes CEILING.MATH as an interoperability function for Excel 2013 or newer. That statement identifies an interchange purpose; it does not prove when Collabora first introduced it or certify every online deployment.

The optional one-unit default can be checked with =CEILING.MATH(-1.2), expected -1, and =CEILING.MATH(1.2), expected 2.

Zero-step behavior, mixed-type conversion, exact native error codes and near-boundary binary-floating-point behavior remain unverified. Retain representative positive, negative and mode controls when exchanging files.

• Collabora Office 26.04: CEILING.MATH.
• Editorial testing standards.

The complete function section was reviewed. Worked results are independently checked expectations; native execution and unlisted edge cases remain unverified.