Men with deeper voices are often thought to have an advantage in both attracting romantic partners and intimidating rivals, an idea largely built on experiments using audio clips alone. However, a new study published in Royal Society Open Science suggests that when listeners can see a speaker’s full body on video, a deeper-than-average voice increases how dominant and physically formidable a man seems without making him more attractive to women. The findings also indicate that deeper voices subtly nudge viewers to guess that a man weighs slightly more, even when his body is visible.
Among human physical traits, the adult voice exhibits one of the largest differences between the sexes, a biological pattern known as sexual dimorphism. Boys and girls have nearly identical voices until around age 11, when a surge of male hormones during puberty causes the vocal folds in the larynx to thicken and the vocal tract, the airway stretching from the throat to the mouth, to lengthen. These anatomical changes lower two main acoustic properties: fundamental frequency, which we hear as voice pitch (how high or low a voice sounds), and formant frequencies, which determine vocal resonance (the rich depth or timbre of a voice).
According to the authors, these rapid pubertal voice changes appear to have been shaped by sexual selection, the evolutionary process in which traits spread either because they appeal to mates, known as intersexual selection, or because they help individuals compete against same-sex rivals, known as intrasexual selection.
Early research relied on audio recordings and pointed toward mate choice, such as a 2005 experiment showing that digitally lowering the pitch and resonance of men’s recorded voices made them sound more attractive to women. Later work shifted weight toward male-to-male competition, including a 2020 study of Amazonian forager-horticulturists in Bolivia that found lowering voice pitch made men sound like better fighters, did not change ratings of prestige, and reduced their attractiveness to local women.
Even the link between deep voices and dominance has been questioned because audio-only experiments strip away visual context. In reality, voice pitch is a poor indicator of a man’s actual height or weight, yet a 2019 study found that judging low-pitched male voices as dominant in audio clips was tied to listeners mistakenly assuming the speakers were taller than they really were.
To test whether vocal masculinity still shapes impressions of attractiveness and dominance once a speaker’s physique is visible, lead author James E. Rutter, who earned his doctorate in psychology at Durham University, and co-author Lynda G. Boothroyd of Durham University conducted two experiments pairing digitally altered voices with full-body videos.
“Basically, past studies showed that, when you take recordings of men speaking and then digitally lower their pitch, they sound stronger, more physically formidable, and more respected by their peers,” Rutter told PsyPost. “But they also sound physically bigger too, so it could just be that listeners imagine a larger man speaking when you take his audio and lower its pitch. We wanted to know whether these perceptions still held up once a listener could see the full physique of the speaker.”
“This had quite big implications for the field, because the literature had been suggesting that men’s voices drop during puberty primarily to sound formidable rather than attractive, but it’s a lot harder to make that argument if they only sound more formidable when you can’t see them,” he added.
In their first study, the researchers filmed 17 young white men with British accents, aged 19 to 32, standing from head to toe in identical neutral clothing while counting from one to five (an 18th model was excluded due to poor audio quality). Recruited from a rowing club, a university powerlifting society, and by word of mouth, the men varied widely in build, ranging from 165.5 to 193.0 centimeters (about 5 feet 5 inches to 6 feet 4 inches) in height and 46.6 to 128.3 kilograms (about 103 to 283 pounds) in weight.
Using acoustic software, the authors set each clip’s pitch to very deep (75 Hertz), deep (95 Hertz), average (115 Hertz), or high (135 Hertz), and combined those with three vocal resonance levels (masculinized by 10 percent, unchanged, or feminized by 10 percent) to create 12 video versions per man.
The team recruited 1,466 U.S. adults aged 18 to 36 via the online platform Prolific, excluding 121 responses that failed an audio check or showed low effort. Each participant saw only one randomly chosen video of each of the 17 speakers and rated a single trait: heterosexual women rated attractiveness (from 0 to 10), men rated either physical strength (0 to 100) or fighting ability (the percentage of men the speaker could beat in a fight), and a mixed-gender group rated social dominance (how respected and influential the man seemed among peers, from 0 to 100). Separate groups rated silent versions of the 17 videos. The authors shared their rating data publicly, minus the models’ heights and weights, which could identify them.
Analyzing the ratings showed that a deeper voice did not make a man more attractive than average once his body was visible. Although overall models linked lower vocal frequencies to higher appeal, group comparisons indicated that this pattern was driven by a dislike of feminized voices rather than a preference for extra-masculine ones.
For pitch, women rated the high-pitched (135 Hertz) clips below every other pitch level and rated the very deep (75 Hertz) clips as less attractive than the deep (95 Hertz) ones, while the difference between the deep (95 Hertz) and average (115 Hertz) clips was not statistically significant. For vocal resonance, clips with feminized resonance scored below the other two resonance levels, whereas the difference between masculinized and unchanged resonance was not statistically significant.
In contrast, lowering voice pitch and resonance steadily increased all three dominance ratings in a straight line, making men appear stronger, better at fighting, and more socially influential. “When we made their voices higher than average, they received lower ratings for attractiveness, strength, physical formidability, and social dominance (i.e. respect and influence among peers),” Rutter explained. “However, when we made their voices deeper than average, they appeared more dominant physically and socially, but not more attractive.”
The finding about strength caught him off guard. “I wanted to run the study because I genuinely had no idea what the results would be, but I think I was most surprised to see that men actually looked stronger when we made their voices deeper,” Rutter said.
Even so, visual appearance outweighed the voice on every measure: silent-video ratings accounted for roughly 12 to 38 percent of the variation in judgments, while the voice changes accounted for about 1 to 5 percent. For example, dropping voice pitch by 20 Hertz raised a man’s estimated fighting success by just 1 percentage point, such as moving from beating 50 percent of men to 51 percent. Notably, adding video also changed which trait the voice affected most. Whereas audio-only studies usually find that vocal masculinity shifts physical dominance the most, here the voice had its largest effect on social dominance (accounting for 4.8 percent of variation, versus 1 to 2 percent for the other traits), while physical dominance relied most heavily on what viewers could see.
Interactions between voice pitch and the models’ height, weight, or body mass index (BMI) were not statistically significant, which the authors take as evidence that visual and vocal cues operated largely independently. The one notable interaction involved the men’s looks: raising voice pitch hurt the attractiveness of men rated as more attractive in silent videos more steeply.
These results align with an earlier study of male vocal pitch and hormone levels, which evaluated audio recordings alone rather than pairing voices with full-body video. That study similarly found that deeper voices were strongly linked to perceived dominance among men while having a much smaller effect on attractiveness to women.
At the same time, the lack of an attractiveness boost for deeper-than-average voices stands in tension with an audio-only experiment on vocal averageness and pitch, which found that while vocal averageness did not affect appeal, lower pitch in male audio clips was associated with higher attractiveness ratings. The findings also diverge somewhat from an earlier video experiment on digitally manipulated voice pitch and facial hair, which showed only the speakers’ faces and found that while beards only increased dominance, voices deeper than average boosted both dominance and attractiveness.
Because the first experiment could not establish why deeper voices still made men look tougher when their bodies were visible, a second study tested whether vocal cues distort size estimates. The authors recruited 542 men aged 18 to 36 on Prolific to watch the same 204 videos after viewing a baseline reference clip showing a sample speaker’s actual height and weight: 307 U.S. participants guessed each man’s weight in pounds, while 235 participants from Germany, Australia, and New Zealand guessed height in centimeters. Lowering pitch and resonance led viewers to guess that the men weighed slightly more, explaining 0.10 percent of the variation in weight guesses (adding 0.34 kilograms per 20-Hertz drop in pitch and 0.45 kilograms for masculinized resonance), whereas effects on height estimates were not statistically significant.
“Participants also estimated that the men were heavier, but not taller, as their voices were deepened, which is interesting because there’s virtually no correlation between someone’s weight and the pitch of their voice,” Rutter noted.
In the authors’ reading, this slight upward shift in perceived weight may contribute to why deeper voices continue to increase impressions of physical formidability on video. However, because separate groups of participants rated dominance and estimated weight, the study cannot directly show that weight perceptions drove the dominance ratings.
The authors note that if that extra perceived weight were muscle, the 0.34-kilogram shift would represent roughly 2.4 percent of an average man’s upper-body muscle or 7.1 percent of his arm muscle, and combat sport weight classes are typically separated by only 3 or 4 kilograms. They also suggest that even a 1 percentage point edge in perceived fighting ability could deter rivals often enough to yield evolutionary benefits over many generations.
There are a few things to keep in mind when interpreting these findings, starting with who appeared in the videos and who rated them. All raters lived in Western, industrialized countries, where reactions to vocal pitch often differ from those in traditional, small-scale societies. In addition, the 17 white British models included rowers and powerlifters, with BMIs ranging from underweight to obese.
“These effects were small,” Rutter said. “People relied a lot more on the visuals for all ratings, but the impact of the voice was still very significant. Also, we deliberately recruited men with very different body types to be filmed, which probably downplayed the impact of the voice changes.”
“For example, our study featured men with BMIs from 17 to 40, whereas hunter-gatherer populations tend to exhibit much less variation in BMI,” he continued. “If we’d used body types more relevant to our evolutionary history, we probably would have produced bigger results.”
The vocal recordings were also brief and tightly controlled, consisting of men counting from one to five in a flat tone over three to five seconds, yielding only about one second of voiced speech. In everyday life, people judge potential partners and rivals during spontaneous conversations involving full sentences, emotional expression, and vocal qualities like breathiness, which may influence attractiveness more strongly than pitch or resonance alone. The authors also pointed out that they tested an extra-deep pitch at 75 Hertz without a matching extra-high version at 155 Hertz, which may have muted the overall relationship with attractiveness.
Finally, how the videos were filmed and how the questions were asked may have shaped the size estimates in the second study. Although the men were visible from head to toe, their T-shirts and trousers covered their torsos and legs, which the authors suggest could have left enough uncertainty about muscle mass for a deep voice to nudge weight guesses upward.
At the same time, filming everyone from the exact same distance and angle may have made judging stature relatively easy, and asking for concrete units like pounds and centimeters rather than subjective 0-to-10 ratings may have limited the influence of the voice. Future research could test whether these patterns hold in non-Western societies using natural speech and models of similar build.
“I’m looking at vocal attractiveness more in my next paper, which investigates whether people sound more attractive when suffering from a cold,” Rutter concluded. “This caught my eye (or ear) because I noticed a lot of people telling me they preferred their voices when they were ill, but I couldn’t think of a sensible reason why. Generally perceptions of health and attractiveness are so intertwined, they often feel like the same thing, so I was interested to see why this might not apply to the voice.”
The study, “Low voice pitch, when accompanied by video, increases perceived dominance but not attractiveness,” was authored by James E. Rutter and Lynda G. Boothroyd.