How to SUMIF across a row (horizontal SUMIF)
✓ Verified in LibreOffice 25.8.7.3Conditional sums when your categories run left-to-right instead of top-to-bottom.
The formula
| App | Formula | Notes |
|---|---|---|
| Excel | =SUMIF(B1:H1,"Q1",B2:H2) | Criteria range and sum range are both horizontal — SUMIF doesn't care about orientation, only that shapes match. |
| Google Sheets | =SUMIF(B1:H1,"Q1",B2:H2) | Identical. |
| LibreOffice Calc | =SUMIF(B1:H1,"Q1",B2:H2) | Identical. |
How it works
SUMIF works sideways exactly as it does vertically — the header row is the criteria range and the numbers row is the sum range: the two Q1 columns contribute 10 + 20 = 30. The only real rule is that both ranges must have the same shape and alignment. COUNTIF/AVERAGEIF/SUMIFS are equally orientation-agnostic; people just rarely see horizontal examples.
Verified, not just documented
We ran =SUMIF(B1:E1,"Q1",B2:E2) in LibreOffice 25.8.7.3 (headless, with forced recalculation) and it returned 30 — exactly the expected result. Every formula here is confirmed by actually executing it.