try http://www.cme.com/trading/prd/equity/pricelimits.html for CME products. measure the points from the previous settlement price - look for the close of the last RTH (regular trading hours ) session.
Worksheet for the lazies: Index, Settlement Price, 5% limit overnight session (points), Minimum trade Price ES 1325.50 70 1255.50 NQ 1849.50 105 1744.50 ER2 674.50 37 637.50 YM 12106 650 11456 All indices went limit down on tuesday morning.
yes, that's right, should have said measure from previous settlement price which may or may not be the last traded price.