Chastity Cage Sizing: How To Measure For Your Tube & Ring

Posted by Beautiful Voice on

Measuring tapes and cock cages
Choosing the right size chastity cage is an integral part of the chastity process. It should be tight enough to prevent erections, but not so tight that it causes pain.
When you get it right though, it can be a breath of fresh air. You can wear it as long as you want, with no issues at all with comfort, chafing or irritation.
So what do you need to do to find your ideal fit?

Cock Cage Measurements – The Anatomy of a Chastity Cage

The anatomy of a cock cage
To find the dimensions you need, first you need to understand the different parts of a cock cage. These are the ring, and the tube (sometimes called the body or just the cage).
Each part will need different measurements to be taken before you can find your ideal fit.

Measuring for the Ring

Here at Lock the Cock, most of our products feature either a single, adjustable ring or a set of 2-5 rings of various sizes. These rings are measured by their diameter, which is the distance from one side of the ring to the other.
A perfectly sized ring will fit snugly behind your testicles but will continue to allow blood to flow to the penis. It should not pinch or leave your equipment feeling numb or uncomfortable.
Because the penis is round and plump in shape, it is quite difficult to find the diameter of it. Instead, we recommend measuring the circumference, which is the full distance around your cock. Once you have this measurement then you can perform a simple calculation to work out the diameter.

Measuring the Circumference

Measuring for the ring
To obtain accurate dimensions of your cock's circumference, we recommend first taking a hot bath or shower. This will leave your penis flaccid but encourage the active flow of blood so that your final result will account for the slight swelling of the equipment as blood passes through. For best results, take your measurement immediately upon getting out of the shower or bath, before your body has had any time to cool down.
Measuring the circumference
You can use either a cloth measuring tape, or a piece of string or ribbon. If you use string or ribbon, you’ll need to make a mark on it where the two pieces cross over, then place it next to a ruler to find the length of the string.
Simply wrap the tape measure or string all the way around your penis and testicles, at the base of the penis.
Once you've got your circumference, simply divide it by pi (approximately 3.14) to obtain the diameter. Below are a few examples of such calculations using popular cock ring sizes:
Popular Ring Sizes
  • Circumference behind testicles of 157mm (6.1 inches) ÷ 3.14 = ring diameter of 50mm (1.96 inches)
  • Circumference behind testicles of 141mm (5.5 inches) ÷ 3.14 = ring diameter of 45mm (1.77 inches)
  • Circumference behind testicles of 125mm (4.9 inches) ÷ 3.14 = ring diameter of 40mm (1.57 inches)

Measuring for the Tube

Measuring for the tube
Finding the right length for the long "tube" portion of your new cage is a significantly simpler process. You can use a straight ruler to measure the length of your equipment from base to tip.
As with the ring, we recommend doing this right after a hot bath or shower, so that the penis is completely flaccid but there is some active blood flow to the area.
Stand up tall with your back straight. Place the edge of the ruler against the base of your penis and lay it flat on the top of your penis. Then, in order to obtain the most accurate measurement, press the ruler firmly against your pubic bone. This prevents any belly fat from getting in the way.
Measuring the length
You may wish to ask a partner or trusted friend to help you with this, as reading the ruler while remaining in a straight, tall posture can be difficult.
When choosing a cage, do not look for the tube which most closely matches your equipment in length. Instead, subtract between 1/4 inch and 1/2 inch (6 and 13 mm) from your measurement. For example:
  • Flaccid penis length of 4 inches = 3.5 or 3.75 inches.
  • Flaccid penis length of 3 inches = 2.5 or 2.75 inches.
  • Flaccid penis length of 2 inches = 1.5 or 1.75 inches.
  • Flaccid penis length of less than 2 inches = 1 or 1.25 inches.
The ideal chastity device tube will fit your penis tightly but not constrict it to the point that it cannot release urine. Ideally, your urethral slit will lie against the opening at the end of the tube. The width of the tube will be narrow and completely prevent you from achieving erection, no matter how aroused you may become.
Whatever size you need, Lock the Cock has you covered. There are plenty of options in our collection for all kinds of slave.
Standard models including the Eyes on Her Prize, the Inescapable, and The Dark Cobra offer a variety of sizes the should comfortably hold most penises. Small models like the Flat Gatling and the Steel Holy Trainer Nub are much smaller, hiding your cock away completely.
You should also consider extra features as well as the length. Cellmate can be locked and unlocked by a phone app, a timer function, and shock function. The Shock the Cock is a simpler model which also provides electrostim functions.

Choosing Your Cock Cage

Various Size Cock Cages
Once you’ve got your measurements, it’s time to go shopping!
Depending on the type of device you want, you can explore our various chastity cage collections to see what’s on offer. Keep your measurements handy and compare them to the sizing information on each product page to make sure it will fit snugly.
An important part to consider is the gap. This is the area of space between the ring and the tube, and finding the right gap can make a huge difference to the comfort of the cage. If your scrotum hangs particularly low or forward, then you’ll want a cage with a larger gap. If your scrotum is high and tight to your body you’ll want a smaller gap.
Most of the time you won’t need to worry about this, but if you are having trouble finding a comfortable cage then paying more attention to the gap size can improve the situation.
If you’re looking for more advice on choosing a cage, then make sure to check out our buyers guides listed below:

Enjoy Chastity!

When breaking in a new cage, make sure to walk around for the first few hours wearing it. Use the toilet and ensure that urine can freely escape as you relieve yourself. If you feel any pain, pinching, numbness, or other discomfort, let your keyholder know immediately. Wearing a chastity device long term should be difficult and uncomfortable, but it should not cause you any long-term pain or damage.
That's it! You've got yourself a perfectly sized, perfectly fitted cock cage to wear for as long as you desire, or rather, as long as your keyholder desires. Wondering what "cums" next? Well, we can say it's definitely not you… but you can take a look at our Chastity Play and Chastity Games guides to pick up a few ideas!
Chastity Basics Written By Beautiful Voice

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About The Author

Beautiful Voice

The Beautiful Voice of the chastity community demands to be heard! Your experiences, your advice, your thoughts. We explore all of these through the Beautiful Voice pen name, and post relevant content to the chastity experience under this name.

Everyone is different after all, so we want our content to provide all of these perspectives. What works for one slave doesn’t work for all of them. One kind of Mistress is different to another. But most importantly, we all love chastity.

Chastity is… an escape, a passion, a journey, a goal, a kink, a fetish, a lifestyle.

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