Key Takeaways
- The finger-length testosterone test supposedly tells you if your testosterone (T) levels are high or low, based on how long certain fingers are.
- The test suggests that if your index finger is longer than your ring finger, your T levels are low, and if your ring finger is longer than your index finger, your T levels are high.
- This test isn’t a reliable way to measure testosterone. Instead, get your levels checked by a doctor or with a reliable at-home kit.
In an ideal world, you’d be able to skip the long wait at the doctor’s office to check your testosterone levels.
What if there was simple way to check your hormone levels?
A method known as the “finger-length testosterone test” claims that you can learn if your testosterone (T) levels are low by just looking at your hands: more specifically, at the ratio between your ring finger length and index finger length.
But is there any truth to this claim?
I know what you’re thinking, how accurate could the length of your fingers and the ratio between your ring and index fingers be in measuring your testosterone?
In this article we’ll take a look at how accurate this test and the 2D:4D ratio are, as well as other markers of testosterone levels, and some key steps to improve your hormones.
What is the finger-length testosterone test?
The finger-length testosterone test suggests the ratio between the length of your index finger (your second digit or 2D) and the length of your ring finger (your fourth digit or 4D) indicates if your testosterone level is low.
This ratio is said to be a marker of someone’s androgen exposure in the womb before birth.
A lower 2D:4D ratio (if your ring finger is longer than your index finger) supposedly means you have higher testosterone levels, reflecting higher exposure to testosterone before birth (according to the test).
On the other hand (pardon the pun), with a higher 2D:4D ratio — meaning your index finger is longer — the theory says you have low T levels, reflecting lower exposure to testosterone before birth (according to the test).
How to do the finger-length testosterone test
Want to try the finger-length testosterone test yourself?
Simply hold out your hand level and with the palm facing towards you. Keep your ring, middle, and index fingers placed next to each other to see whether your ring or index finger is longer.
Is the finger-length testosterone test accurate?
While the finger-length testosterone test sounds like it would make checking your testosterone levels a lot easier (and save you time and money), unfortunately, there isn’t much scientific evidence to support it.
Results from one study from 2019 suggest that men with a lower 2D:4D ratio may have a greater social network and more social capital.
Meanwhile, results from another study suggest that men with lower 2D:4D ratios were perceived as more masculine and more aggressive by women and performed better in sports.
While these studies looked at levels of androgen exposure in the womb and personality type, aggression, and more, there doesn’t seem to be more data on whether or not a longer index finger means low testosterone levels.
For now, it’s safe to say finger-length testosterone tests are not a reliable way of assessing testosterone levels.
The best ways to measure testosterone
Just because the finger-length test isn’t the most accurate marker of testosterone levels, doesn’t mean there aren’t other options.
If you’re concerned you have low testosterone, there are signs of low T to look out for:
Your doctor may ask about your symptoms and also use blood tests to check your testosterone levels for both total and free testosterone, with the latter being a more accurate indicator of low testosterone.
But getting an appointment, driving to the doctor, and waiting ages for results is a hassle.
Luckily, you can actually measure important markers like testosterone from home with at-home testosterone testing that allows you to measure total testosterone, free testosterone, luteinizing hormone (LH) and follicle-stimulating hormones (FSH), and more.
How to treat low testosterone
If you have low testosterone there’s several effective testosterone treatments to get your levels in check.
TRT is a popular option that you may choose if you’re struggling with symptoms like fatigue, increased body fat, or sexual issues like low sex drive or erectile dysfunction.
Lifestyle changes like switching to an optimized testosterone diet, regular exercise, getting enough sleep, and stress reduction may also be recommended to boost testosterone.
Know your testosterone levels. Grow your testosterone levels.
The truth is, there’s no secret, magic way to know your testosterone levels outside of getting your blood tested and reviewing your levels.
While there may be some evidence to suggest the 2D:4D finger test works, it’s no replacement for lab tests that really work.
Disclaimer: The contents of this article, including, but not limited to, text, graphics, images, and other information, is for information purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. The content is not meant to be complete or exhaustive or to be applicable to any specific individual's medical condition. You should consult a licensed healthcare professional before starting any health protocol and seek the advice of your physician or other medical professional if you have questions or concerns about a medical condition. Always talk to your doctor about the risks and benefits of any treatment. Never disregard or delay seeking professional medical advice or treatment because of something you have read on this site. Maximus does not recommend, endorse, or make any representation about the efficacy, appropriateness, or suitability of any specific test, products, procedures, treatments, services, opinions, healthcare providers or other information contained herein. Maximus is not responsible for, nor will they bear any liability for, the content provided herein or any actions or outcomes resulting from or related to its use.
References:
- Bailey, A. A., & Hurd, P. L. (2005). Finger length ratio (2D:4D) correlates with physical aggression in men but not in women. Biological psychology, 68(3), 215–222. https://pubmed.ncbi.nlm.nih.gov/15620791/
- Buchholz, V. N., Mühle, C., Risk Factors, S. U., Kornhuber, J., Lenz, B., Gmel, G., Foster, S., Marmet, S., & Studer, J. (2019). Lower Digit Ratio (2D:4D) Indicative of Excess Prenatal Androgen Is Associated With Increased Sociability and Greater Social Capital. Frontiers in Behavioral Neuroscience, 13, 489680. https://www.frontiersin.org/journals/behavioral-neuroscience/articles/10.3389/fnbeh.2019.00246/full
- Sizar O, Leslie SW, Pico J. Androgen Replacement. [Updated 2023 Nov 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534853/
