Being the President of the United States is no easy job, and it takes a certain level of intelligence to get the job done. A UC Davis researcher looked into each President’s approximate IQ; keep reading to see who was considered the smartest.

44. Ulysses S. Grant – IQ: 130.0

With the lowest IQ on this list, Ulysses S. Grant’s intellect still packed a punch at around 130, which is considered above-average. The 18th president struggled in school and was even called “useless” due to his lack of academic enthusiasm.

Despite this, he still managed to achieve greatness and inspire a country in the process. In 1868 he won the presidential election and eventually became the Commanding General of the United States Army in the Civil War. He even circumnavigated the globe to meet with other world leaders, the first president to do so.

43. George W. Bush – IQ: 138.5

As the 43rd president of the United States and the son of a former president, George W. Bush seemed destined to fulfill this leadership role himself. Serving two terms from 2001-2009, Bush had an estimated IQ of 138.5 and a very prestigious college education, so his intelligence was certainly above-average.

Believe it or not, young George attended public school in his home state of Texas before being transferred to Phillips Academy in Massachusetts, where he excelled both in academics and sports. He later attended Yale and then completed his MBA at Harvard Business School before leading his country.

42. James Monroe – IQ: 138.6

James Monroe might’ve had a lower IQ than many of his fellow presidents, at around 138.6. Still, history has recognized Monroe as a high-performing leader, with the ability to run the country as well, if not better than many of his counterparts. He even served as ambassador to France before picking up the mantle of President.

Monroe had a series of successes during his run, including negotiating for the Louisiana Purchase and establishing the Monroe Doctrine in opposition to colonial European influence in the US. He also regularly promoted “intelligence among the people as the best means of preserving our liberties.”

41. William Howard Taft – IQ: 139.5

Though he wasn’t considered the best student as a young man, William Howard Taft was ambitious, a trait that was encouraged by his parents. This ambition took him far in life; He became the 10th Chief Justice and later the 27th president of the United States in 1909, with an estimated IQ of 139.5.

Taft became the only president to ever hold both positions, securing himself a place in American history forever and proving his brilliance regardless of IQ level. In his single term as president, he found great satisfaction in his work and accepted that “We are all imperfect. We can not expect perfect government.”

40. James Buchanan – IQ: 139.6

Originally a Federalist party member, James Buchanan later switched to Democrat, fearing his party would eventually end. This pragmatic attitude reflected his approzimate 139.6 IQ, and though he was a smart and practical figure in politics, he has not escaped the critique of many Americans.

Buchanan has been heavily criticized over the years, particularly in his decisions to ignore the issues of slavery in the Southern States. As a result, he is not viewed kindly by many people. Though considered by some to be one of the least accomplished presidents, he still had some successes in his career.

39. Zachary Taylor – IQ: 139.8

While he wasn’t well known for his academic pursuits, Zachary Taylor had an impressive track record in the United States military, leading troops to victory in several battles during the Mexican-American War. These successes bolstered his election campaign, leading him to become the 12th US president, with an IQ of around 139.8.

But becoming president wasn’t always his plan. “The idea that I should become President seems to me too visionary to require a serious answer,” Taylor stated before his election. “It has never entered my head.” Unfortunately, he didn’t get a chance to fully prove himself as he passed away just 16 months after taking office.

38. Andrew Johnson – IQ: 139.8

Andrew Johnson did what may seem unthinkable to many – he became the 17th president of the United States of America despite never receiving a formal education. But with an estimated IQ of 139.8 plus natural ambition and determination, he overcame the odds, first serving as Abraham Lincoln’s vice president until 1865.

Johnson was appointed to the office shortly after his predecessor’s assassination, but he was impeached in 1868 due to conflicts with Congress. His public reaction was this – “Let them impeach and be damned.” Despite the impeachment, Johnson was later elected to the Senate, which was unusual for a former president.

37. Harry S. Truman – IQ: 139.8

Another vice president turned president, Harry S. Truman, was vice president to Franklin D. Roosevelt. He also took on the role of Commander in Chief after Roosevelt’s passing. He then took office in 1945, serving two terms as president and implementing both the Marshall Plan and the Truman Doctrine.

With an IQ of around 139.8, Truman had much to say about what it meant to be a leader, famously stating, “Men make history and not the other way around. In periods where there is no leadership, society stands still. Progress occurs when courageous, skillful leaders seize the opportunity to change things for the better.”

36. Warren G. Harding – IQ: 139.9

An unusual background for a president, William G. Harding ran an Ohio newspaper before joining the State Senate. He decided to run for President in 1920 but initially had little public favor. That eventually changed, and by the end of the elections, he was named the 29th President of the United States.

With an estimated 139.9 IQ, Harding used his intelligence to make tremendous improvements to the government and Republic. He tragically passed away during his first term, unable to see all of his plans to fruition. Unfortunately, many scandals involving Harding came to light after his death, altering his reputation forever.

35. George Washington – IQ: 140.0

It only makes sense that the first president to ever grace the Oval Office was a clever and capable man. With an approximate IQ of 140, George Washington served as President from 1789 to 1797 and was often referred to as ‘The Founding Father of America,’ a title he didn’t take lightly.

Despite the accolades, he was a humble man. He once said, “Lest some unlucky event should happen unfavorable to my reputation, I beg it may be remembered by every gentleman in the room that I, this day, declare with the utmost sincerity, I do not think myself equal to the command I am honored with.”

34. Gerald Ford – IQ: 140.4

According to the UC Davis study, the 28th President had an IQ of 140.4. Taking office in 1974, Gerald Ford had a significant impact on the country’s trajectory, choosing to sign the Helsinki Accords, which brought the States one step closer to easing the Cold War tensions. But his sights hadn’t always been set on the office.

As a young man, he pursued a career in law while working part-time as an assistant football coach. He became vice president in 1974, before taking over as President after Richard Nixon’s resignation. During his maiden speech, Ford announced, “My fellow Americans, our long national nightmare is over.”

33. Lyndon B. Johnson – IQ: 140.6

Unlike some others on this list, Lyndon B. Johnson knew his fate from a very young age. At 12-years-old he insisted he would one day become President of the United States. And with an estimated IQ of 140.6, he was right. in 1963, he was sworn in as the 36th President after John F. Kennedy’s assassination.

Johnson’s legacy is mixed. On the one hand, he has been heavily criticized for his role in the Vietnam War, but he also received praise for the stringent laws he passed to promote civil rights, environmental protection, and more. He once said, “Books and ideas are the most effective weapons against intolerance and ignorance.”

32. Calvin Coolidge – IQ: 141.6

The 30th President was a quiet and reserved man, famous for his care with words, even writing, “The words of a president have an enormous weight and ought not to be used indiscriminately.” This philosophical stance reflected his approximate 141.6 IQ and served him well during his political career.

He became the Governor of Massachusetts before being appointed Vice President for Warren G. Harding. After Harding’s passing in 1923, Coolidge took over as leader and was well-regarded for his time as President, restoring the public’s faith in government and the White House.

31. Herbert Hoover – IQ: 141.6

Despite his IQ of around 141.6, Herbert Hoover did not excel in school. His disdain for formal education was clear, and aside from the bible, he did very little reading. He soon dropped out of school at age 13, yet still made it into Stanford University after failing all but one entrance exam.

Things only went up from here, as Hoover was appointed to office in 1929. He expressed immense gratitude for the opportunities he was given, saying, “My country owes me nothing. It gave me, as it gives every boy and girl, a chance. It gave me schooling, independence of action, opportunity for service and honor.”

30. Ronald Reagan – IQ: 141.9

Ronald Reagen had an estimated IQ of 141.9, according to a UC Davis study. He eventually became one of the most popular presidents in modern American history, serving two terms between 1981 and 1989. Reagen loved sports as much as politics; He played football and swam competitively in high school and college.

But not everyone knows that before he became president, Reagan was a Hollywood icon, starring in multiple B-movies. He was also a famous jokester, once saying, “I have left orders to be awakened at any time in case of national emergency – even if I’m in a Cabinet meeting.”

29. Richard Nixon – IQ: 142.9

Richard Nixon’s path to the presidency was a complicated one and continued to be so during his time in office. But with an IQ of approximately 142.9, natural academic abilities, and outstanding debate skills, he was expected to go far in life. He was even offered a grant to attend Harvard University.

After completing his first degree, Nixon’s brother fell sick, and the future president had to take over the family business. Soon after, he was also granted a scholarship for Duke University of Law. He once said, “The American dream does not come to those who fall asleep.”

28. George H. W. Bush – IQ: 143.0

“Like father, like son” is an appropriate saying for this former President. With an IQ of around 143, he likely passed on his intelligence to his progeny George W. Before taking the country’s highest office, George H.W. attended Yale University, one of the most prestigious schools in the United States.

Bush enjoyed an illustrious career in politics. He joined the House of Representatives, became a UN ambassador, Vice President, and then President. But this impressive man had a soft side, even saying in an interview, “Let me give you a little serious political advice. One single word: puppies. Worth the points.”

27. William McKinley – IQ: 143.4

William McKinley is a famous example that success and failure aren’t always set in stone. Before he began his political career, he struggled to get through formal education, with an estimated IQ of 143.4. McKinley dropped out of two tertiary institutions, Allegheny College and Mount Union College.

But he didn’t let this deter him, eventually completing his degree at Albany Law School in New York and eventually became the 26th President of the United States. Later on in his career, he said, “That’s all a man can hope for during his lifetime – to set an example – and when he is dead, to be an inspiration for history.”

26. James Polk – IQ: 143.4

With an IQ of approximately 143.4, America’s 11th President, James Polk, probably would’ve excelled in an academic environment. Unfortunately, due to poor health and illness, Polk had to spend most of his childhood and teenage years being home-schooled.

But his parents seemed to have done a great job with young James’ schooling, as he aced his entrance exams and was accepted as a Mathematics undergrad at the University of North Carolina. Polk made history when he became president at age 49, the youngest man to hold office at that time!

25. Grover Cleveland – IQ: 144

Grover Cleveland had a non-traditional track record, claiming two non-consecutive terms as the 22nd and 24th US President. With an estimated IQ of 144, it’s no surprise he claimed the position both in 1885 and later in 1893, winning public support in both of his election campaigns.

Despite his advanced intelligence, Cleveland firmly believed that there was always more to learn and made it his mission to do so. He once said, “I know that I am honest and sincere in my desire to do well. But the question is whether I know enough to accomplish what I desire.”

24. Barack Obama – IQ: 144

The former President has an IQ of 144, per Sociosite. The 44th President attended Columbia University in New York, earning a degree in political science before receiving magna cum laude from Harvard Law. He even helped coordinate voter registration campaigns during Bill Clinton’s 1992 presidential campaign!

Obama will always be remembered for inheriting the financial crisis that began in 2007 and implementing a stimulus package of economic measures to combat the crisis. Many critics applaud him for aiding millions of Americans during his presidency and providing tax relief to the working class during his two terms.

23. Andrew Jackson – IQ: 145

As the Democratic Party’s founding father, it makes sense that Andrew Jackson would have an admirable IQ of around 145. He was elected President in 1829, becoming the seventh man in US history to do so, after serving as a Major General in the US Army for some years.

Despite being in such an elevated position, Jackson had no problem admitting his faults. He believed that this was the mark of a true leader. “Any man worth his salt will stick up for what he believes is right,” he said. “But it takes a slightly better man to acknowledge instantly and without reservation that he is in error.”

22. Dwight Eisenhower – IQ: 145.1

Before becoming the 34th President, Dwight Eisenhower enjoyed a remarkable career in the US Military, rising to the role of five-star general. These achievements elevated him to the position of a two-term president with an IQ of about 145.1. According to the man himself, he put a lot of heart into his work.

“I believe when you are in any contest, you should work like there is always to the very last minute a chance to lose it,” Eisenhower later said. “This is battle, this is politics, this is anything. So I just see no excuse if you believe anything enough for not putting your whole heart into it. It is what I do.”

21. Benjamin Harrison – IQ: 145.4

Intelligence, ambition, and leadership seemed to run in Benjamin Harrison’s blood. After all, his own grandfather had served as President decades before, and his great-grandfather was founding father Benjamin Harris, after whom he was named. Young Benjamin started his career as a lawyer before turning to politics.

With an estimated IQ of 145.4, Harrison served one term before being ousted by Grover Cleveland. “I knew that my staying up would not change the election result if I were defeated,” he reportedly said after results came in. “While if elected, I had a hard day ahead of me. So I thought a night’s rest was best in any event.”

20. Martin Van Buren – IQ: 146

Martin Van Buren entered the Oval Office with an impressive intellect and an estimated IQ of 146. But his career had been even more impressive – as a founder of the Democratic Party, a governor of New York, and secretary of state and Vice President to Andrew Jackson, Van Buren was indeed qualified.

But Van Buren himself didn’t deny the difficulties of leading the country, despite his extensive resume and vast intelligence. “As to the presidency, the two happiest days of my life were those of my entrance upon the office and my surrender of it,” the eighth President once said.

19. Rutherford Hayes – IQ: 146.3

Rutherford Hayes came from unlikely beginnings, growing up in rural Ohio with his father, a farmer. But against all odds, he graduated top of his class, with an IQ of around 146.4. He left home to pursue a degree at Kenyon College and went on to study at Harvard Law School before starting his own law firm.

Hayes believed that the best way he could change society was to set a good example everywhere. He once said, “Personally, I do not rely on force – not even the force of law – to advance moral reforms. I prefer education, argument, persuasion, and above all the influence of example.”

18. William Henry Harrison – IQ: 146.3

William Henry Harrison lived an impressive life, with a predicted IQ of 146.3. But it came to an unfortunate end sooner than expected. Despite his many successes, he became the first President to pass away during his term, succumbing to severe illness after only 31 days in the Oval Office.

Despite his tragic legacy, Harrison achieved many things in his life. Studying medicine in both Virginia and Philadelphia, the man eventually quit that particular field to enlist in the army. He later became Major General and Commander-In-Chief before being elected President.

17. Franklin Pierce – IQ: 147

Franklin Pierce achieved great success at a comparatively young age. In 1853, he became the youngest person at that time to be elected President at age 47. According to UC Davis studies, Pierce had an unusually high IQ of 147, which likely helped pave the way to his presidency.

Pierce believed in looking to the past for inspiration and guidance, once saying, “The founders of the Republic dealt with things as they were presented to them, in a spirit of self-sacrificing Patriotism and as time has proved, with a comprehensive wisdom which it will always be safe for us to consult.”

16. John Tyler – IQ: 148.1

After President William Henry Harrison passed away, Vice President John Tyler found himself being thrust into an unexpected position of power. Perhaps this lack of preparation was why he didn’t get much public support, despite his high intelligence, with an estimated IQ of 148.1.

“My own personal popularity can have no influence over me when the dictates of my best judgment and the obligations of an oath require of me a particular course,” Tyler said in response to his unpopularity. “Under such circumstances, whether I sink or swim on the tide of popular favor is, to me, a matter of inferior consideration.”

15. Millard Fillmore – IQ: 149.0

From poor beginnings as the son of tenant farmers, this native New Yorker pulled himself out of the claws of poverty and went on to take the most crucial title in the country. This achievement may have been helped by the fact that Millard Fillmore had an IQ of around 149, despite his lack of formal education.

He joined the US House of Representatives and was Vice President before taking the position as President in 1850. Fillmore famously said that “The man who can look upon a crisis without being willing to offer himself upon the altar of his country is not for public trust.”

14. Abraham Lincoln – IQ: 150.0

One of the most famous leaders in US history, Abraham Lincoln, had an impressive estimated IQ of 150. He served as the 16th US President in 1861 and became known for navigating the country through the American Civil War. He abolished slavery before his death in 1865, something he is rightly lauded for to this day.

Before he was assassinated, this iconic historical President showcased his modesty and desire to encourage the population when he said, “I happen temporarily to occupy this big White House. I am living witness that any one of your children may look to come here as my father’s child has.”

13. Franklin Roosevelt – IQ: 150.5

Franklin Roosevelt was destined for success from a young age, and not just because of his high IQ, estimated to be 150.5. The 32nd President studied under private tutelage from infancy to his early teenage years before being sent to a respectable boarding school. He went on to study at Harvard and Columbia Law School.

Roosevelt continued to study what interested him into his adult life, and one of the greatest lessons he was given? To always try, no matter what. He once said, “It is common sense to take a method and try it. If it fails, admit it frankly and try another. But above all, try something.”

12. Chester Arthur – IQ: 152.3

The 21st US President lived a life that’s been highly respected no matter the time period. Before being elected to the Oval Office, he had a fulfilling career as a lawyer and abolitionist, representing civil-rights figure Elizabeth Graham in a case that eventually led to New York streetcars’ desegregation.

With an IQ of around 152.3, he had his own ideas of what made a successful person. “Be fit for more than the thing you are now doing,” Arthur said. “Let everyone know that you have a reserve in yourself; that you have more power than you are now using. If you are not too large for the place you occupy, you are too small for it.”

11. James Garfield – IQ: 152.3

Another intelligent man who managed to strongarm his way out of poverty, James Garfield, thrived with his impressive IQ, about 152.3. The key to his success was a good education, and he went to law school to become an attorney before being appointed head of state. He rejected the idea that class status dictated self-worth.

“There are men and women who make the world better just by being the kind of people they are. They have the gift of kindness or courage or loyalty or integrity,” Garfield said. “It really matters very little whether they are behind the wheel of a truck or running a business or bringing up a family. They teach the truth by living it.”

10. Theodore Roosevelt – IQ: 153.0

One of the most admired presidents in history, Theodore “Teddy” Roosevelt, was homeschooled from a young age. A naturally gifted young man with an IQ of about 153, he was accepted into Harvard University, where he had an impressive academic career in Science and Philosophy. Today he is remembered for his progressive policies.

He believed that surviving hardship was the key to a successful life. “Nothing in the world is worth having or worth doing unless it means effort, pain, difficulty,” said Roosevelt. “I have never in my life envied a human being who led an easy life. I have envied a great many people who led difficult lives and led them well.”

9. John Adams – IQ: 155.0

John Adams had an astounding IQ, estimated to be 155, yet he did not consider himself a genius. This renowned leader believed that the more he learned, the less he knew. “The longer I live, the more I read, the more patiently I think, and the more anxiously I inquire, the less I seem to know,” he said.

With his passion for education and life lessons, Adams was one of the men who led the fight for independence when young America tried to escape Great Britain’s grip. As America’s second President, Adams played a crucial part in the American Revolution.

8. Woodrow Wilson – IQ: 155.2

These days, Woodrow Wilson is most remembered for leading the United States to victory in World War I, which led to his particular and influential foreign policy brand, known as Wilsonianism. It’s estimated that he had one of the highest IQs of any president, at 155.2.

Wilson was quite open about his life ambitions. “You are not here merely to make a living,” he once said. “You are here in order to enable the world to live more amply, with greater vision, with a finer spirit of hope and achievement. You are here to enrich the world, and you impoverish yourself if you forget the errand.”

7. Donald Trump – IQ: 156

With one of the highest IQs on the list, several sources, including The Times Herald, have reported Donald Trump’s IQ at 156. The 45th president attended the Wharton School of Business at the University of Pennslyvania and has since then dubbed himself a “very stable genius.”

According to multiple sources, Trump has always been fascinated by people’s IQ, including his own cabinet during his presidency. He openly discussed his Supreme Court picks, Neil Gorsuch and Brett Kavanaugh, as having excellent Ivy League educations, and his aides believed it was a prerequisite of his to attend a top-tier law school.

6. Jimmy Carter – IQ: 156.8

Like many men on this list, Jimmy Carter enjoyed a prestigious political career, serving as Georgia’s State Senator and Governor for some years before becoming Commander In Chief. Carter has an estimated IQ of 156.8, but it seems his term as President was less enjoyable, despite winning a Nobel Peace Prize in 2002.

It seemed retirement from the Oval Office suited him well. Carter later made light-hearted fun of the pressures and downsides of a presidential career, saying, “My esteem in this country has gone up substantially. It is very nice now that when people wave at me, they use all their fingers.”

5. Bill Clinton – IQ: 159.0

Few presidents are as well-known as Bill Clinton, the 42nd President of the US. Young Bill attended Georgetown University in Washington, DC, so it’s no surprise he had his eye on the presidency from an early age. With a high IQ of about 159, he went on to study at Oxford and Yale Law School, where he met his future wife, Hilary.

The former President shared his key to success – he never, ever gave up. “If you live long enough, you’ll make mistakes. But if you learn from them, you’ll be a better person,” Clinton shared. “It’s how you handle adversity, not how it affects you. The main thing is never quit, never quit, never quit.”

4. John F. Kennedy – IQ: 159.8

It’s commonly said that when John F. Kennedy was assassinated in 1963, the whole world was watching. And few presidential deaths have been mourned as widely as his. But he is also remembered for his natural charisma and intelligence, with an estimated IQ of 159.8.

The impressive leader served in both the House of Representatives and the Senate before proudly stepping into the Oval Office. JFK made his principles clear when he said, “Life is never easy. There is work to be done and obligations to be met – obligations to truth, to justice, and to liberty.”

3. James Madison – IQ: 160.0

Known as the “Father of the Constitution,” James Madison is remembered for his lengthy list of accomplishments. He helped to publish the Federalist Papers and draft the Bill of Rights, and of course, became the fourth US President. With an incredible IQ of around 160, it makes sense that he prized knowledge above all else.

“Knowledge will forever govern ignorance, and a people who mean to be their own governors must arm themselves with the power knowledge gives,” Madison once said. “A popular government without popular information or the means of acquiring it is but a prologue to a farce or a tragedy or perhaps both.”

2. Thomas Jefferson – IQ: 160.0

He may have been the third US President, but Thomas Jefferson is the second-smartest President in American history, with an estimated IQ of 160, alongside James Madison. Jefferson is commonly remembered as the man who wrote the Declaration of Independence.

Before taking office, Jefferson was recorded saying, “I had rather be shut up in a very modest cottage with my books, my family and a few old friends, dining on simple bacon, and letting the world roll on as it liked than to occupy the most splendid post, which any human power can give.”

1. John Quincy Adams – IQ: 175.0

John Quincy Adams is widely considered the most intelligent US President who has ever lived (so far). According to a UC Davis study, he had an impressive IQ of 175, 15 points above both Thomas Jefferson and James Madison. Adams was a certified genius and made his career as a diplomat, lawyer, and of course, president.

It’s only sensible that such a brilliant man would hold knowledge and education in the highest regard. “To furnish the means of acquiring knowledge is … the greatest benefit that can be conferred upon mankind,” Adams said. “It prolongs life itself and enlarges the sphere of existence.”