Following his breathtaking, 11 length Queen Anne Stakes victory at Royal Ascot on Tuesday, Frankel's official rating has risen by two pounds to 140.
It makes him officially the best since another Prince Khalid Abdulla-owned horse, Dancing Brave, in 1986 who ended his career with a rating of 141.
Apart from his own 138 in the JLT Lockinge Stakes at Newbury last month, Frankel's 140 puts him a massive 16 pounds clear of the next best performances in the 2012 QIPCO British Champions Series - the Epsom victories of Camelot in the Investec Derby and St Nicholas Abbey in the Diamond Jubilee Coronation Cup (sponsored by Investec) and So You Think's Prince of Wales's Stakes triumph at Royal Ascot yesterday.
All three Aidan O'Brien-trained horses earned a British Horseracing Authority (BHA) performance rating of 124 to share top ranking in the Middle Distance division.
Excelebration's 125 when beaten five lengths in the JLT Lockinge Stakes keeps him in second place to Frankel in both the Mile division and the overall Series rankings, though he ran well below his best when finishing more than twice as far behind Frankel on Tuesday, for which he was rated just 115. The Queen Anne third, Side Glance, was rated 114.
Most Improved was awarded a rating of 116 following his St James's Palace Stakes triumph. In the light of that race, the ratings for the QIPCO 2000 Guineas have been dropped by two pounds with Hermival, third at Newmarket and second at Ascot, receiving the same 114 rating for both performances. Gregorian, who was a head back in third in the St James's Palace, was also rated 114.
Camelot's Guineas win drops to 119 and runner-up French Fifteen goes down to 118, but still well above Most Improved.
Hong Kong raider, Little Bridge now tops the Sprint division on a rating of 120 following his fine King's Stand Stakes victory at Royal Ascot on Tuesday.
The King's Stand runner-up, Bated Breath, took a step forward for the season to 118 after recording 116 in the first sprint of the Series, the betfred.com Temple Stakes at Haydock Park. Sole Power ran second to Bated Breath that day and was third in the King's Stand, with both performances rated 115.
So You Think's 124 in yesterday's Prince of Wales's Stakes was a pound below his current official mark of 125.
The runner-up Carlton House, posted 119 - the same mark as he ended last season - while the unlucky third, Farhh, posted a career best 118 and must have the potential to go higher as the season progresses.
Dominic Gardiner-Hill, the BHA's mile handicapper, said: "Frankel's win in the Queen Anne was one of the most visually stunning I have seen in my time as a handicapper and I'm sure was a superior performance to his win in the Lockinge and therefore his rating will rise to 140.
"In the modern era, Dancing Brave is the highest rated horse we have had on 141 and I wouldn't want to put Frankel above him on what he achieved on Tuesday.
"If you look at the quality of the field that Dancing Brave beat in the 1986 Arc, it was chock-full of Group One winners and although Frankel finished a long way clear, beating Side Glance, Indomito and Windsor Palace (Group Two and Three horses at best) does not entitle him to be considered the superior horse at this stage in my opinion."
Rod Street, Chief Executive of the British Champions Series, said: "Frankel has led the way in the QIPCO British Champions Series at every stage, ever since the very first race last year when he blitzed his rivals in the QIPCO 2000 Guineas.
"It looks like he has three Series races left in his career to try to achieve the highest official rating ever, the Coral-Eclipse or the QIPCO Sussex Stakes, followed by the Juddmonte International and then either the Queen Elizabeth II Stakes or the QIPCO Champion Stakes on QIPCO British Champions Day.
"We have to enjoy him while we can as we will surely never see another like him, but now our attention turns to the world's second best horse, Aussie superstar Black Caviar.
"Can she put up as visually stunning a performance as Frankel in Saturday's Diamond Jubilee? A sensational end to the week may await!"