Harry Davis' 16th-minute penalty put Crewe in the driving seat but Lewis Grabban ensured the spoils were shared.
A terrible clearance by goalkeeper Rhys Taylor went straight to Byron Moore and as he raced into the penalty area he was hacked down from behind by Jason Taylor and Davis made no mistake from the spot on 15 minutes.
Rotherham could have had an equaliser after 24 minutes when Alex Revell was only just wide with a header from Ben Pringle's cross and they should have levelled after 32 minutes.
An attempted clearance in a goalmouth scramble cannoned straight to leading marksman Grabban, but Steve Phillips was off his line in a flash to block the shot.
Phillips was beaten minutes later by Danny Harrison's header from a left-wing corner, but Ashley Westwood cleared off the line.
Rotherham finally got the equaliser after 63 minutes. Pringle's high floating cross was allowed to bounce inside the six-yard box and Grabban nipped in to poke home his 16th of the season.
Revell headed over from six yards out and then penalty appeals were waved aside when Pringle was brought down near the end and then the ball struck a visiting hand in stoppage time as Crewe held on for their fourth draw in a row.
Att: 2,447 (137)
Source: PA