COUNTIFS evaluates multiple conditions and counts only cells where every condition is true. When counting between two numbers, you specify the same range twice — first with the lower-bound criteria such as ">=70" and second with the upper-bound criteria such as "<=89". For each row, COUNTIFS checks the value against both conditions: if it is at least 70 AND at most 89, the row counts. If either condition fails, it does not. This is pure AND logic, which is what you want for a range. The choice of >= versus > for the lower bound and <= versus < for the upper bound controls whether the range is inclusive or exclusive. For discrete whole-number data like test scores graded in whole points, ">=70" and "<=89" works cleanly. For continuous data like measured amounts, you might prefer strictly greater than the lower bound. The same pattern extends to dates because dates are stored as serial numbers — between two dates is just a special case of between two numbers. If you need to count against a single threshold, the
count cells greater than a value and
count cells less than a value formulas handle those cases with the simpler
COUNTIF function.