Here's a script to tell you how big your table(s) are, subtotaled by indexes, with a grand total. Includes LOBs, and excludes dropped pages.
SELECT CASE WHEN GROUPING(t.name) = 0 THEN t.name ELSE 'GRAND TOTAL' END AS 'Table Name'
, CASE WHEN GROUPING(i.name) = 0 THEN i.name ELSE 'TABLE TOTAL' END AS 'Index Name'
, SUM(au.total_pages) * 8 / 1024 AS 'Allocated MB'
, SUM(au.used_pages) * 8 / 1024 AS 'Used MB'
FROM sys.allocation_units au
LEFT JOIN sys.partitions pHobt
ON au.container_id = pHobt.hobt_id
AND (au.type_desc = 'IN_ROW_DATA' OR au.type_desc = 'ROW_OVERFLOW_DATA')
LEFT JOIN sys.partitions pLob
ON au.container_id = pLob.partition_id
AND au.type_desc = 'LOB_DATA'
JOIN sys.indexes i
ON (i.object_id = pHobt.object_id AND i.index_id = pHobt.index_id)
OR
(i.object_id = pLob.object_id AND i.index_id = pLob.index_id)
JOIN sys.tables t
ON i.object_id = t.object_id
WHERE au.type_desc != 'DROPPED'
AND t.type_desc = 'USER_TABLE'
AND COALESCE(pHobt.rows, pLob.rows, 0) > 0
AND t.name LIKE '%MyTable%'
GROUP BY ROLLUP(t.name, i.name)
ORDER BY t.name, i.name
