Upfrog is a theorized speedrun strategy within the Top-Hat Tower in the Cap Kingdom. It involves skipping the frog capture near the base of the tower, and instead climbing up to and capturing one of the frogs halfway up the tower. Unlike the frogs at the bottom of the tower, the frogs on the upper level do not have an associated cutscene, eliminating the need to input the cutscene skip sequence.
The name "Upfrog" is based on the word updog, which is famously used as a practical joke.
The Upfrog strategy involves skipping the first set of frog captures at the base of the Top-Hat Tower interior using movement similar to that used in Minimum Captures runs, and instead capturing one of the frogs among the second set, halfway up the tower. The key advantage to this is that the frogs in the second group do not trigger the cutscene that normally plays when Mario captures a frog for the first time. Although this cutscene can be skipped, doing so takes approximately a second.
While it is possible to clear the entire tower without capturing any frogs, the movement for doing so becomes too slow in the second half to consider skipping the second set of frogs in mainstream speedruns.
It is important to note that Upfrog has not actually been proven to be faster than the original strategy of capturing the frog at the bottom of the tower. However, some speedrunners have created spliced videos to show how fast Upfrog could potentially be, and it comes within mere frames of the fastest clips for the original movement. It is often theorized that Upfrog is ultimately the faster strategy, and may make an appearance in tool-assisted speedruns.