Carroll rescued a point in the 87th minute after it looked like they were heading for back-to-back defeats, following David Cotterill's opener.
But the contribution was shrouded in controversy on a Swansea side who believed they had done enough to win a third game on the bounce.
They were left seething after believing Carroll should have been sent off for an elbow on Garry Monk. And the striker then rubbed salt into the wounds by levelling in the closing stages.
Thumping: Andy Carroll (right) leaps to power home Newcastle's equaliser
Swansea boss Paulo Sousa said: 'I think it was a sending-off. It was an elbow and I've seen the video of the incident. I wouldn't call for the sending-off, but we didn't agree with the referee's decision at the time. We can't do much about it now.
'I'm only angry, though, as we should have won the game rather than blame the referee.
'It can be a cruel game. They are the best side in the league but we are the best team playing football in the Championship. We deserved more out of this. We can't be frustrated and must be proud at the way we played. We were the better side on the day and deserved to win by miles.'
Time to celebrate: Andy Carroll has just levelled for Newcastle
A poor first half was transformed after the interval. Nathan Dyer first saw his long-range strike sail inches past Steve Harper's post and, when Cotterill's raking pass had freed Darren Pratley, team-mate Dyer took it off his toes in a mix-up to let off Newcastle.
But there would be no good fortune moments later, as Cotterill decided to take it on himself as the pressure finally paid off with his stunning 45th-minute strike.
Pratley picked out Cotterill and the winger did the rest with a curling shot which flew into the top corner. Ashley Williams went close to adding to Swansea's lead in the 70th minute and nobody would have had any complaints. But he headed just over the bar after Alan Tate had flicked on Cotterill's corner.
Swansea substitute Gorka Pintado then missed a golden chance to seal the win when he miskicked with the goal at his mercy.
Carroll would have had no qualms if referee Andy Woolmer had given him his marching orders, rather than the yellow card he did receive for raising his arm at Monk.
And he made pay when he headed home substitute Leon Best's cross, as Swansea conceded for the first time at the Liberty Stadium in more than 10 hours.
Newcastle boss Chris Hughton said: 'My first impression was that Andy was competing for the ball. It wasn't a red card. I never felt it was anything but a yellow card.'I have to give credit to my players; we are not playing as well as we can but to come away with a point is a good result.
'They are in form in the league. We could have played better than we did. On the balance of play and the way we approached the game at the end, I thought we deserved an equaliser.
'What the last week has shown is that it's a very tough division. A anyone who felt we would walk away with it is wrong. When you have dips in form and don't play well, it's important to get something from the game.'
Swansea (4-5-1): De Vries; Tate, Williams, Monk, Bessone (Rangel 7min); Dyer (Butler 80), Orlandi, Allen, Pratley, Cotterill; Kuqi (Pintado 74). Subs (not used): Cornell, Gower, Trundle, Richards. Booked: Orlandi.
Newcastle (4-5-1): Harper; Simpson, Coloccini, Hall, Van Aanholt; Routledge, Smith, Nolan, Guthrie, Lovenkrands (Best 66); Carroll. Subs (not used): Krul, Williamson, R Taylor, Pancrate, Kadar, Ranger. Booked: Coloccini, Carroll.
Referee: A Woolmer (Northamptonshire)
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