The ICC released its updated rankings one day after confirming Rabada's two-Test ban, which will force him to miss the rest of the four-Test series against Australia that is currently level at 1-1.
The Proteas are yet to reveal whether they will appeal the code-of-conduct charge resulting from Rabada's physical contact with Steve Smith on day one of the second Test.
Cricket South Africa is seeking legal advice and is set to confirm today whether it is lodging an appeal.
Rabada reclaimed top spot on the ICC's Test bowling charts after claiming 11-150 in Port Elizabeth, a man-of-the-match effort that included a stack of key wickets at clutch moments.
The 22-year-old is now 15 points above England veteran Jimmy Anderson on the rankings, with fifth-placed Josh Hazlewood the top-ranked Australian.
South Africa skipper Faf du Plessis suggested Rabada still had room for improvement.
'A lot has been said about KG's amazing rise,' du Plessis said.
'I honestly still think KG will get better. I'm really excited to see what's going to happen in his future.
'He's got the best strike-rate in the world [of any current player]. I don't think you have to say too much more.
'To have him in your side as a captain is a huge pleasure.
'Both teams have very high-class, reverse-swing bowlers but what makes KG so special for me is he does it both ways at pace … and he doesn't give a lot of bad balls away.'
The series continues in Cape Town next Thursday.
Rabada noted earlier this week he was 'letting the team down' with his behaviour, but also made it clear he was unhappy to be sanctioned for brushing shoulders with Smith.
'Honestly, I didn't even feel the contact in that moment because I was just so pumped up,' Rabada said.
'I didn't feel any contact at all. If I did it deliberately then I wouldn't have contested.'
Rabada also revealed some of the more light-hearted barbs directed his way on day one in Port Elizabeth, where he was sent out as nightwatchman after bowling 21 overs.
'Some of the Australians made some jokes. They said I've been bowling the whole day and now I've come to bat. They called me Braveheart, etc etc. It doesn't stop,' he said.