Here is a list of all of the major changes we made to Excel 12 in the area of limits.
The total number of available columns in ExcelOld Limit: 256 (2^8)New Limit: 16k (2^14)
The total number of available rows in ExcelOld Limit: 64k (2^16)New Limit: 1M (2^20)
Total amount of PC memory that Excel can use Old Limit: 1GBNew Limit: Maximum allowed by Windows
Number of unique colours allowed a single workbookOld Limit: 56 (indexed colour)New Limit: 4.3 billion (32-bit colour)
Number of conditional format conditions on a cellOld Limit: 3 conditionsNew Limit: Limited by available memory
Number of levels of sorting on a range or tableOld Limit: 3New Limit: 64
Number of items shown in the Auto-Filter dropdownOld Limit: 1,000New Limit: 10,000
The total number of characters that can display in a cellOld Limit: 1k (when the text is formatted)New Limit: 32k or as many as will fit in the cell (regardless of formatting)
The number of characters per cell that Excel can printOld Limit: 1kNew Limit: 32k
The total number of unique cell styles in a workbook (combinations of all cell formatting)Old Limit: 4000New Limit: 64k
The maximum length of formulas (in characters)Old Limit: 1k charactersNew Limit: 8k characters
The number of levels of nesting that Excel allows in formulasOld Limit: 7New Limit: 64
Maximum number of arguments to a functionOld Limit: 30New Limit: 255
Maximum number of items found by “Find All”Old Limit: ~64k (65472)New Limit: ~2 Billion
Number of rows allowed in a Pivot TableOld Limit: 64kNew Limit: 1M
Number of columns allowed in a Pivot TableOld Limit: 255New Limit: 16k
Maximum number of unique items within a single Pivot FieldOld Limit: 32kNew Limit: 1M
Length of the MDX name for a Pivot Table item; also the string length for a relational Pivot TableOld Limit: 255 charactersNew Limit: 32k
The length at which fields’ labels are truncated when added to PivotTable; this also includes caption length limitationsOld Limit: 255New Limit: 32k
The number of fields (as seen in the field list) that a single PivotTable can haveOld Limit: 255New Limit: 16k
The number of cells that may depend on a single area before Excel must do full calculations instead of partial calculations (because it can no longer track the dependencies required to do partial calculations)Old Limit: 8kNew Limit: Limited by available memory
The number of different areas in a sheet that may have dependencies before Excel must do full calculations instead of partial calculations (because it can no longer track the dependencies required to do partial calculations)Old Limit: 64kNew Limit: Limited by available memory
The number of array formulas in a worksheet that can refer to another (given) worksheetOld Limit: 65kNew Limit: Limited by available memory
The number of categories that custom functions can be bucketed intoOld Limit: 32New Limit: 255
The number of characters that may be updated in a non-resident external workbook referenceOld Limit: 255New Limit: 32k
Number of rows of a column or columns that can be referred to in an array formulaOld Limit: 65,335New Limit: Limitation removed (full-column references allowed)
The number of characters that can be stored and displayed in a cell formatted as TextOld Limit: 255New Limit: 32k