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Your Ape Index and 10 Other Really Super Important Measurements

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Do you know your ape index? Do you know how to measure it? Do you know what an ape index is? Do you even climb, bro?

These are all very important questions. Some climbers believe that a positive ape index can provide a competitive advantage. It has even been claimed that certain training techniques can increase your Ape Index, but this claim is not without controversy. For now, let’s discuss what the ape index is and how to measure it, and also examine a series of other useful measurements that every climber should be aware of.

The Ape Index

The ape index is the length of your arm span compared to your height. This is sometimes expressed as a ratio, with Da Vinci’s “Vitruvian Man” alluding to the idea that the perfect ratio is one, which is to say that arm span and height should be equal.

For climbers, a more useful way to express the ape index is to subtract height from arm span, giving a value that is either positive, neutral or negative. A positive index is seen as advantageous for climbers. I think mine is probably minus 17.

The Sloth Index

This measurement is similar to the ape index, but excludes the torso. To find your sloth index, subtract the length of the leg (hip to heel) from the length of the arm (deltoid to fingertip). The sloth index is then expressed as positive, neutral or negative.

Folks who love to layback claim that a neutral sloth index is fantastic, because then they don’t have to bend their legs. It also allows for hand-foot matches that are as smooth as silk. On the other hand, a neutral or positive sloth index will make you look like a total weirdo when you’re not climbing, so most people are comfortable with a negative one.

The Snake Index

Always given as a ratio, the snake index is an indication of how wide you can open your mouth. To find this measurement, take your hardest redpoint grade and divide it by how many people you sprayed about your send to.

For this to work, you’ll need to convert any pagan grades to a mathematically logical grading system. Only one exists—the Australian Ewbank grade. For example, if you ticked a 5.13a at the Red River Gorge, or a 7c+ in Kalymnos, you’ll need to convert that nonsense to 28. And then, say you told 56 people, you will have a snake index of .5, which is also known as “proper anaconda.”

The Hobbit Index

The hobbit index is the comparison of hand and foot lengths. For most people, these two appendages increase in size according to a positive linear effect. In laypersons terms, small hands mean small feet, and large hands mean large feet.

There are, of course, outliers. One of these is my good friend Erik Griffith who has the hands of a carnival ride operator and feet the size of baby dolphins. Despite this oddity, he’s an excellent climber who smashes long Yosemite free climbs on the reg. So the anecdotal evidence (which, according to the comments on any Facebook post, is the only kind which matters) suggests that an inverse hobbit index is consistent with mad crushing.

The Beanie Index

This is an indication of how hard you can boulder, expressed as the number of beanies you own. It’s a well-known fact that Nalle Hukkataival was finally able to tick V17 when his sponsors at Black Diamond sent him a new beanie.

The Insta Index

Without a doubt the most important index on this list, the Insta index measures how wide your reach is as an “influencer.” Always expressed as a ratio, you will need to divide the amount of followers you have by the average amount of likes your posts receive. The great thing about this one is that you don’t even need to climb hard to have an astronomical Insta index. Just make sure you’re good looking, and if not, stare wistfully away from the camera.

The Windex Index

This measurement is becoming increasingly important in the competitive world of industrial rope access, a game in which reach (actual physical reach, not to be confused with the insta index) is king.

Not merely an indication of height, the windex index takes into account muscular and tendon strength as well. To measure, grab a squeegee and reach as high as you can on your tiptoes, holding it for ten seconds. Training will improve the ability for professional window cleaners to reach that little extra, something that may set them apart from others of equal height.

The Index Index

Perhaps one of the trickiest on this list to measure, the index index can vary greatly according to the variability of climbs. Essentially, it is a comparison of the smallest hold on any given climb and the pad size of your fingers, with the idea that smaller fingers will sometimes be able to fit more comfortably on small crimps.

Strong climbers often use the index index as a fantastic and thoroughly scientific excuse when they get absolutely smashed by someone with better technique on something thin and techy.

The Fist Index

This is not what you’re thinking. In something of a continuation of the index index, fist width (which is used as a metric for general hand size) is compared to the crack size on any given route. Also known as the Indian Creek index, it explains why large-mitted climbers often cruise 5.10’s like Supercrack while thin-handed climbers sometimes have trouble even getting off the ground. Then, as grades increase into the 5.12 and 5.11 range, the index index applies and the inverse is true. It’s all very complex and shouldn’t be approached without a solid grounding in particle physics.

The Caldwell-Fiennes Missing Index Index

This is essentially a measurement of how much of a badass you are, based on how hard you can climb versus how many fingers you’ve lost. For example, Tommy Caldwell sent Flex Luthor (5.15a) without the aid of half of his left index finger. Translated into Ewbank, this gives us a grade of 36 multiplied by 0.5 of a finger, giving TC a missing index index of 18. On the other hand, it’s unclear what grades explorer Ranulph Fiennes has ticked, but given that he cut off his own fingertips with a hacksaw in his garden shed, he can give himself whatever index he wants.

Ryan Siacci is the creator of

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