Whether it’s to settle an argument or decide who takes the first kick-off in a football match, the coin toss has been used for centuries.

But when choosing between heads or tails, you may want to reconsider your assumption that the odds are 50/50.

This is because scientists have claimed that a natural bias occurs when coins are tossed.

After flipping coins more than 350,000 times, experts found that the face that was originally facing up returns to the same position 50.8 percent of the time.

This may not seem particularly significant, but the experts behind the new research say it is “overwhelming evidence of same-side bias.”

More physics than chance? Researchers led by the University of Amsterdam said their study had provided “overwhelming evidence of a same-side bias” when it comes to coin tossing.

The numbers: They stated that a natural bias occurs when coins are tossed, causing the side that was originally facing up to return to the same position 50.8 percent of the time.

The study was led by Frantisek Bartos, a doctoral candidate in psychological methods at the University of Amsterdam, who said the importance of bias becomes even more pronounced in the gaming world.

“If you bet a dollar on the outcome of a coin toss 1,000 times, knowing the initial position of the coin toss, you would win $19 on average,” he wrote on X, formerly Twitter.

“This is more than the casino edge for six-deck blackjack against an optimal player ($5), but less than that for single-zero roulette ($27).”

Bartos and his team flipped a coin 350,757 times as part of the research.

‘About a year ago, we embarked on a quest to answer one of the most intriguing questions: If you toss a fair coin and catch it in your hand, what is the probability that it will land on the same side it started on?’ published in X.

“Today we are finally ready to share the results.”

Bartos said the study’s findings showed “compelling statistical support” for the “physical model of coin flipping,” first proposed by Stanford mathematician Persi Diaconis in 2007.

He concluded that “when people toss a normal coin, it tends to land on the same side it started on.”

Another researcher, Stanford mathematician Persi Diaconis, first realized that coin tosses were not random after he and his colleagues managed to set up a coin tossing machine so that one coin came up heads each time (in the photo).

Theory: Diaconis noted that randomness is attributed to the fact that when humans toss a coin, there are a number of different moves that the coin is likely to make.

Diaconis estimated the same side’s result was 51 percent.

“Our data strongly supports this accurate prediction,” Bartos wrote in his paper, “the coins fell on the same side more often than not.”

Diaconis first realized that coin tosses were not random after he and his colleagues managed to set up a coin toss machine so that one coin came up heads each time.

Then, he and his team asked human subjects to do the same thing over and over again, recording the results with a high-speed camera.

Although the results were a little more random, they ended up with a margin of 51 to 49 percent.

Diaconis noted that the randomness is attributed to the fact that when humans toss a coin, the coin is likely to make several different movements.

For example, he showed how coins not only move from one end to the other, but also in a circular motion, like a pizza thrown into the air.

He also discovered that there are ways to toss a coin where it looks like it’s spinning in the air, but it’s not actually moving at all.

Diaconis demonstrated this by tying a ribbon to a coin and showing how in four out of 10 cases the ribbon remained flat after the coin was caught.

Therefore, he and his team concluded that coin tossing had to do with “physics” and not just “randomness.”

“Coins that are thrown naturally obey the laws of mechanics and their flight is determined by their initial conditions,” the researchers wrote in their article.

Bartos agreed.

‘SThe ame-side bias originates from off-axis rotations (i.e., precession or wobble), which can reasonably be assumed to vary among people,” he and his team wrote in a preprint study published in arXiv.

‘Future work may attempt to verify whether “wobbly pitchers” show a more pronounced same-side bias than “steady pitchers.”

Either way, the next time you flip a coin, you might want to consider taking a look at which side is up; could give you a slight advantage in the ’50/50′ odds.