SUM — Excel guide
Adding up — with the range mechanics that separate clean models from fragile ones: what gets skipped, what propagates, and which ranges survive edits.
SUM
Add every number in the given cells and ranges.
- Text and TRUE/FALSE inside ranges are silently skipped — a number stored as text quietly vanishes from your total.
- Any error in the range poisons the SUM; AGGREGATE(9, 6, range) sums around errors.
- Running total: =SUM($B$2:B2) filled down — lock the start, let the end slide.
- Filtered data? SUM ignores the filter; SUBTOTAL(9, range) respects it (109 also respects hidden rows).
- =SUM(A2:A6) survives row inserts inside the range; =A2+A3+A4+A5+A6 doesn't.