FLOOR.MATH in Collabora Office: Round Down with an Optional Negative Mode

• 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.

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

significance defaults to 1, and its sign is ignored. Positive numbers round toward zero. For negative numbers, omitted or zero mode rounds away from zero; any nonzero mode rounds toward zero.

This differs from the signed-step restrictions of FLOOR. Examples use English function names and semicolon separators.

Enter 20, 21, 26 and 28 in A2:A5:

=FLOOR.MATH(A2;7)

Expected rounded quantities are 14, 21, 21 and 28. The corresponding complete-group counts are 2, 3, 3 and 4. Remainders are 6, 0, 5 and 0.

Replacing the step 7 with -7 leaves the rounded results unchanged. Significance describes the spacing, not a choice between upward and downward rounding.

=FLOOR.MATH(-26;7)
=FLOOR.MATH(-26;-7;0)
=FLOOR.MATH(-26;7;1)
=FLOOR.MATH(-26;7;-3)

Expected results are -28, -28, -21 and -21. The two nonzero modes have the same toward-zero meaning. Neither magnitude nor sign of a nonzero mode counts rounding steps.

An exact multiple such as -28 remains -28 under either mode.

Suppose numeric measurements are -1, 0, 6, 7 and 8, with bucket width seven. Fill down:

=FLOOR.MATH(D2;7)

Expected lower bounds are -7, 0, 0, 7 and 7. With the default mode, these correspond to intervals [-7,0), [0,7) and [7,14). A left bracket includes the lower boundary; the right parenthesis excludes the upper boundary.

For -1, the bucket must begin at -7 to contain the value under this convention. Mode one would produce zero, so it would not implement these lower-bound intervals for negative inputs.

Two teams each have 13 units that can be processed only in groups of seven:

=FLOOR.MATH(13;7)+FLOOR.MATH(13;7)
=FLOOR.MATH(13+13;7)

Expected usable totals are 14 and 21. The second formula assumes pooling is permitted. If the teams must keep separate inventories, that higher combined utilization is not available.

=FLOOR.MATH(4.8) is expected to return 4, while =FLOOR.MATH(-4.8) gives -5. For the latter input, mode one with an explicit step of one gives -4.

TRUNC also moves a negative number toward zero, but its optional argument is decimal precision rather than an arbitrary multiple. Do not substitute one parameter meaning for the other.

Collabora documents FLOOR.MATH for interoperability with Excel 2013 or newer. The guide does not infer a Collabora introduction date from that Excel date, nor claim a native export/import test.

Zero significance, text/Boolean conversion, extreme values and exact error labels remain unverified. Use distinct negative controls when validating an imported workbook; positive-only checks cannot expose a reversed negative-mode policy.

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

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