She leads a bunch of India players who have made rapid gains in the rankings after the team's 3-0 sweep over England.
Kaur smashed a match-winning 143 not out off 111 deliveries in the second match in Canterbury.
Opener Smriti Mandhana and Deepti Sharma have also moved up in the latest update that considers performances in the last two matches of that series as well as the IWC series between the West Indies and New Zealand.
Mandhana, a formerly top-ranked batter who scored 40 and 50 in the two matches, has moved up one place to take sixth position while Sharma's unbeaten 68 not out in the third match at Lord's has lifted her eight places to 24th position.
Pooja Vastrakar (up four places to 49th) and Harleen Deol (up 46 places to 81st) are other India players to move up the batters' list while new-ball bowler Renuka Singh has galloped 35 places to take 35th position after grabbing four wickets each in the two matches.
Fast bowler Jhulan Goswami, a formerly top-ranked bowler, retired in fifth position.
England's Danny Wyatt, who scored 65 in the second match, has gained two slots to reach 21st position among batters while Amy Jones is up four places to 30th. Charlie Dean has progressed 24 places to get to 62nd among batters and one slot to 19th among bowlers.
West Indies captain Hayley Matthews has grabbed the No. 1 position for all-rounders in the ODI format for the first time in her career after aggregating 88 runs and grabbing five wickets in a 2-1 series win over New Zealand.