No, Trump is not the fattest president
He probably is lying about his height, though.

“Girthers” suspect that President Donald Trump’s vital statistics are misrepresented, and that he has a serious obesity problem.
Even considering the uncertainty over Trump’s height and weight, he is definitely not the fattest president in history. He might be pushing second place, but it’s hard to be sure.
The first thing to understand is that Trump does seem to have padded his vital statistics. His 2012 driver’s license and 1961 draft card both list a height of 6′2″. In other words, there is an official chain of records stretching from 1961 to 2012 showing him with a height of 6′2″. Trump currently claims to be 6′3″. It is most likely that his actual current height is about 6′1″.

Height reporting errors are common
First, it’s worth understanding that it’s very common for people, especially men, to report heights 1–2″ to their heights. Men’s self-reported heights are generally around 1″ taller than those measured by medical professionals; OKCupid published an estimate that men add an average of 2″ to their height on their online dating profiles.

It is common for a man who reports his height as 6′3″ to actually be 6′1″ or 6′2″. It’s very uncommon for any height measurement, whether a self-report or an official measurement, to be an underreport, so the older reports of 6′2″ are unlikely to be underestimates.
Additionally, people do tend to lose a little bit of height in their old age. From age 30 to age 70, the average man loses about 3 centimeters (1.2″) of height. Usually people don’t re-measure their height regularly after reaching adult age, so this goes unnoticed. Someone who is 6′2″ as a young man may inaccurately measure themselves as 6′3″; but, by the time they reach Trump’s age, will have shrunk to 6′1″.
Pointedly, Trump has been repeatedly photographed looking the same height as people who are known to be 6′1″. Here’s one particularly clear example, with Trump standing right next to Obama on a set of level steps that happen to provide a lot of easy reference lines. President Obama is widely reported as 6′1″, and (as noted above) this figure is unlikely to be less than his actual height.

The horizontal lines of the stairs make it clear that neither one of them is significantly closer or further from the camera. They’re standing on exactly the same level, and the tops of their heads are exactly in line. The most likely scenario, based on the available evidence, is this: Trump was 6′2″ as a young man. However, for one reason or another, he tended to describe himself as 6′3″. In the mean time, he has shrunk to 6′1″ in actual height.
Trump’s weight
A lot of “girthers” say that Trump does not look like he is 239–244 pounds (the weights reported from his recent annual physicals) but is instead near to 300 pounds. They’ve compared his appearance to that of athletes with similar heights and weights, and Trump does look considerably plumper. It’s very hard to be sure of Trump’s weight based on his appearance, for three reasons.
- First, weight fluctuates much more than height.
- Second, Trump is probably not 6′3″. A 244 pound 6′1″ man looks the same as a 265 pound man at 6′3″.
- Third, people of the same weight can look much bigger or smaller, depending on their body fat percentage and condition.

Professional athletes are on one extreme of the scale when it comes to weight versus girth. Additional muscle is distributed differently from additional fat. Donald Trump is thick around the middle; his excess mass is mostly body fat concentrated around his belly. Athletes usually have more of their excess mass as muscle in their limbs.
In addition, muscle is 15% denser than fat. A morbidly obese 240 pound man with 40% body fat displaces the same total volume as a 261 pound professional athlete with 8% body fat. As noted above, the 261 pound athlete will still be narrower around the midsection than the “same size” 240 pound obese man. It’s very easy to understand how people comparing Trump to professional athletes could guess that he’s around 300 pounds.

While it’s possible that reports of Trump’s weight are inaccurate, I think they are more likely close to his actual weight — they are more likely selectively unrepresentative (e.g., weight after fasting for cholesterol test) rather than outright fabricated. Trump may simply be shorter and in poor physical condition. Skipping leg day, having a high body fat percentage, and being a couple of inches shorter is easily enough to explain away a difference of 40–60 pounds of apparent bulk.
The fattest president
Even if Donald Trump was 289 pounds, as alleged in one popular rumor, he would still not be the fattest president. Depending on how we measure “fattest,” he could rank as high as second; but the unquestionable champion heavyweight is still William Howard Taft (1909–1913).

At the beginning of Taft’s presidency, he weighed close to 300 pounds. He left office at a weight of exactly 340 pounds, according to his own reports. Taft’s weight fluctuated a lot during his adult life, and the stress of the presidency probably played a role in pushing him to his peak weight.
At 5′10″, Taft was definitely also shorter than Donald Trump, meaning that his BMI was substantially higher. Even if Donald Trump was 300 pounds and 6′1″, his BMI would be 39.6; Taft’s BMI was 48.8. Now, in Taft’s defense, he was actually in very good condition for his weight. While Secretary of War, he had been one of Teddy Roosevelt’s frequent sparring partners. In college, he’d been a champion heavyweight wrestler. He’s probably one of the most underrated presidential brawlers.
Another hefty president was Grover Cleveland, who was notably hefty and a man of great appetites. At one point, he decided to limit himself to four glasses of beer a day — and ended up ordering his four glasses in 48 ounce steins in order to stick to the limit.

Grover Cleveland clocked in at as much as 280 pounds on a 5′11″ frame, with a BMI of 39. While the rumored 289 pound weight would make Trump heavier than this, it’s very unlikely that Trump is both short enough and heavy enough to exceed Cleveland’s peak BMI. Given the uncertainty surrounding his height and weight, and the fact that “fattest” can be measured in many different ways, Trump ranks somewhere in the range of third to sixth fattest president.