Virat Kohli has gone 71 innings in international cricket without scoring a hundred since hitting 136 in Kolkata against Bangladesh in November 2019. While he has often got starts, he hasn't been able to convert them into big scores. Kohli has passed fifty 22 times since that innings in Kolkata but hasn't managed to hit his 71st international century yet.
One can hardly complain about Kohli's T20I numbers - he has scored 846 runs at a strike rate of 145.11 and an average of 56.40. It can be argued that he has been denied a hundred in that format only owing to its brevity (he was unbeaten of 73, 77 and 80 in the series against England in Ahmedabad early last year). His ODI form has also been excellent: he has ten fifties in his last 19 innings, four of them in successive matches. No other batter going through such a productive run would be subject to so much scrutiny.
However, Kohli has been dismissed in each of his 49 innings in Tests and ODIs since his last hundred, so he probably hasn't run out of time in those innings unlike in T20Is. It's been a rather long drought for Kohli considering he bats in the top four in these formats. For someone who had set a lofty standard of converting every alternate fifty to a century in Tests and ODIs (he hasn't made a T20I hundred yet), this lean patch sticks out like a sore thumb.
The longest streak of successive innings for any batter in men's Tests and ODIs when he was dismissed before scoring a hundred is Kieran Powell's 94 innings. Including Powell, there have been 22 other instances when batters have been dismissed before scoring a hundred in 49 or more consecutive innings in Tests and ODIs like Kohli. However, in none of these instances have these batters matched Kohli's average of 32.57. The closest anyone has come to Kohli's average among these 22 other batters is Alec Stewart, who was dismissed in 49 successive innings without getting a hundred and averaged 27.49 in these innings.
Perhaps Kohli's current lean run is drawing so much attention because it's not usual for someone of his class. Surely enough, none of the aforementioned 22 batters had a combined average of 40, leave alone 50-plus in their Test and ODI careers like Kohli. Kohli has scored over 20000 runs at an average of 54.77 in these two formats. The closest any of these batters comes to Kohli's average is Andrew Strauss, who made 11242 runs in Tests and ODIs at an average of 38.77. That's 16 runs per dismissal lower than Kohli over Strauss' entire career. Strauss is also the closest of these batters in terms of hundreds in these formats. He made 27 to Kohli's 70.
If we consider the longest streaks without a hundred for batters in the top five in Tests and ODIs irrespective of whether the batter was dismissed or not, there are 32 streaks longer than Kohli's. Even in this list, without the benefit of not-outs, Kohli ranks fifth in terms of average. Desmond Haynes went through 70 successive innings from March 1991 to April 1993 without getting a hundred but averaged the highest among these 32 batters at 35.77. For those statistically inclined the longest someone in the top five went without a hundred (where no hundreds were scored by the batter, but counting only innings in the top five) is Stephen Fleming's 108 innings (which included 25 fifties) from June 1998 to November 2001 before he got a century in the Perth Test of 2001-02.
It's not the worst of century droughts cricket has seen, but then Kohli has been unlike any other batter before him when it came to converting starts. Consider this - over seven different stretches of 49 innings in Tests and ODIs from August 2017 to January 2019, Kohli had made 17 hundreds. This was out of the 26 or 27 times he had crossed 50 in those 49-innings blocks. Kohli has now gone 71 innings without scoring an international century including in T20Is. Compare this to his best streak of 71 innings in international cricket - which he enjoyed over different separate periods - when he scored 19 hundreds. Don Bradman made 28 hundreds in 71 Test innings split by World War II. Sachin Tendulkar also made 19 hundreds in 71 innings in Tests and ODIs from March 1998 to November 1999. These are the only batters who have been as prolific as Kohli, or better. That's the standard Kohli fans have been used to.