Strap On Sizing Guide

How to measure yourself for strap-ons?

To measure a vagina, you will need a vibrator (if possible), or an alternative object which is long, clean and has a smooth surface.

To begin, either you or your partner lay on their back with legs spread. The vagina needs stimulating at this point. Once aroused, you can start sliding the vibrator or alternative object into the vagina. Once the furthest point is reached in the vagina, mark this on the vibrator/ alternative object.

This is the strap on length (for the dildo or vibrator) which the vagina can handle. To measure circumference or girth, fingers can be slid into the vagina until the limit is reached.

When this point has been reached, wrap the tape measure around the fullest point to find the circumference/girth that the vagina can accommodate comfortably.

How Do You Measure Sex Toys?

Generally speaking there are four measurements you should be familiar with.

Length: The vertical length of the toy from the two farthest points. We sometimes refer to this as total length as well.

Insertable Length: The length of the toy designed to be safely inserted.

Width (or diameter): The distance between the two sides of the toy.

Girth (or circumference): The circumference of the toy which is relevant to insertable toys.

Sizing for hollow strap-ons

A hollow strap-on is mostly worn by men who have a smaller penis, so for these, the primary size that needs to be measured for is the male penis. This is to make sure they can fit their penis inside the hollow canal.

While length is never a problem, these hollow strap-ons are measured in diameter rather than circumference.

To measure, you need to get an erection, or for men who have erectile dysfunction, as much of an erection as is possible. When you are stimulated, take the soft tape measure and wrap it around the largest part of the shaft. This will be the circumference measurement.

Now you’ll need to divide this number by 3.14 (pi) on the calculator to find the diameter. Once you have done this, you are then able to choose the size that will fit you.

Internal canal diameters range from around 1.25 inches, and go upward to around 1.5 to 2 inches for larger hollow strap-ons.

Sizing for vibrating strap-ons

Both the length and the circumference/girth of a vibrating strap-on needs to be measured for the receiver and not the wearer of the strap-on harness.

Vibrating strap-ons can be found in a range of sizes that range from around 5 inches and incrementally increase up to approximately 7 to 8 inches of insertable length. Circumference availability begins at around 3 inches, and at the larger end of the scale they can be around 6 inches round.

Sizing for strap-on compatible dildos

Strap-on or harness compatible dildos are designed to give a unique feel to the receiver. They can also come in a varying size ranges but are limited because of the nature of the harness.

You can find insertable lengths of strap-on compatible dildos at around 5 to 6 inches and then larger varieties of between 7 to 8 inches. As these insertable lengths are not in a huge range, you only need to measure the vagina for the circumference or girth it can accommodate.

Circumferences or girths of strap-on dildos can be found from the bottom end of the range at about 3 inches, and at the top end of the range at approximately 6 inches.

Sizing for strap-on dildos and harnesses

Measuring for a strap-on harness is not like sizing for a sex toy. They are adjustable, but it is vital to find the right size to avoid them being too tight or too loose.

These can come in sizes which relate to US dress size, and you can find these in sizes that fit dress size 4 to 30. To measure accurately, you can ask a partner, or you can do it yourself.

To find the ideal size, you just measure around the waist and note down the size.

Next, you will need to measure around the upper part of the thigh where the harness will sit. Again, take the tape measure and wrap it around the thigh so it sits snugly underneath the buttock cheeks. Once you have this measurement, note it down with the other measurement.

Strap on harnesses are usually adjustable from around 15 inches up to about a 70-inch waist measurement allowance.