Use `INDEX` to return a value from a range by row and/or column position
Use `MATCH` to find the position of a lookup value in a range
Combine them as `=INDEX(return_range, MATCH(lookup_value, lookup_range, 0))`
Use `0` in `MATCH` for an exact match
Make sure `lookup_range` and `return_range` are the same size
Use `MATCH` to locate the row number, then `INDEX` to return the corresponding result
For two-way lookup, use `=INDEX(data_range, MATCH(row_lookup, row_headers, 0), MATCH(col_lookup, col_headers, 0))`
Use `MATCH` with `1` for approximate match on ascending sorted data
Use `MATCH` with `-1` for approximate match on descending sorted data
Wrap with `IFERROR` if you want to handle missing matches
Use absolute references when copying formulas across cells
Keep lookup values consistent in type and format with the lookup range