Sizing yourself for anal toys is very different than for vaginal toys. In most cases, it’s all about stretching the anus for anal sex or allowing the user to get larger for using bigger anal toys.
The image below illustrates different dimensions for butt plugs.
Measuring how far the anus can stretch is vital to prevent tearing. So, to do this, you will need: lube, a tapered object and/or a partner. You also need a fabric measuring tape. You can do this sizing solo, but it is difficult to get a good measurement.
The way to do it is to rest on all fours or by leaning over something so you are comfortable. Then, your partner needs to apply plenty of lube to the anus and (the object they are using) or their fingers.
When you are relaxed, they can begin easing into your anus. It is vital not to let them go too far in. This can cause problems with your butt toy.
Once they reach the limit with several fingers or the tapered object, they need to mark how far they inserted. Once they pull their fingers or the object out, you can take the tape and wrap it around the fullest part where they have marked.
This will be the maximum your anus can stretch until you are accustomed to that size. If the manufacturer works in diameter, then divide this number by pi (3.14) to find the width/diameter using a calculator.
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.
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 toys.
Anal toy types
Sizing for anal douches
Anal douches are intended as a hygienic way of cleaning the rectum for anal play. Because of this, they don’t require sizing for circumference or diameter, and only the length needs to be considered.
Some douches come with maximum insertable lengths of 2 to 4 inches. You can also do the measurement solo, but if a partner can, it will be relatively easier.
Our top picks for anal douches
Sizing for anal vibrators
Anal vibes can be hard to measure for by yourself, and it can be helpful if you have a partner to assist. The insertable length will be different from the overall length. At this point, there should be a flared base or testicles to stop the vibrator going too far.
Butt vibrators can range from less than 2 inches in circumference, and reach up to over 8 inches.
Finding the length you can insert into your anus can be more difficult. If you already own an anal toy, you can measure the insertable length, or you can choose from the ranges which are more common. Insertable length can be from around 5 inches for smaller models, or up to 12 inches and above for some models. If in doubt, start small.
Our top picks for anal vibrators
Sizing for butt plugs
Butt plugs are designed to stretch the anus and give a fuller feeling inside the rectum. These need anus sizing for a comfortable depth, and also how wide the anus will be stretched by the broadest part during insertion.
Our top picks for butt plugs
Sizing for glass butt plugs
Because glass butt plugs will not be as strong as steel, they will come with a thicker neck and shorter insertable lengths that range up to 5 inches. For these, you only need to size up for the circumference of the glass butt plug.
Because these are generally smaller, you can find circumferences of between two and three inches at the small end, and then they range up to between 4 and 5 inches at the top.
Our top picks for glass butt plugs
Sizing for inflatable butt plug
Sizing yourself for these will only be what the device is like to insert. They are inflatable so the end size can be much more significant. These do come in longer varieties, so anus depth also needs to be measured as well as the circumference.
Ranges of circumference for inflatable butt plugs are found at around 3 inches and can range up to 10 to 12 inches.
Our top picks for inflatable butt plug
Sizing for jeweled butt plugs
Jeweled butt plugs are mainly made from solid materials so they won't adapt to the body. They also have the flared base that sits between the buttocks. The base will be measured in diameter while the bulb part of the butt plug is measured in circumference.
Their typical insertable lengths are around 4 inches and are pretty standard as penetration is not the focus here.
Our top picks for jeweled butt plugs
Sizing for large butt plugs
What these lack in insertable length, they make up for in circumference. Measuring the anus isn’t so much for what size is comfortable; it’s to see how much you can stretch to fit one of these large butt plugs inside.
Circumferences of large plugs can range from 4 to 5 inches all the way to 9 or 10 inches.
Our top picks for large butt plugs
Sizing for prostate toys
Sizing the anus for a prostate massager is a little different from any other male sex toy. This will take a partner to help as it can make things easier when it comes to taking measurements.
The overall length advertised will be different to insertable length, and it is the insertable portion you need to focus on. Along with this, is the widest part of the prostate massager and what is comfortable when it stretches the anus.
Because the prostate is located a few inches inside the anus, many prostate massagers are in the length range of 4 to 6 inches of insertable length. Girth can range from a slim 2 inches up to a thicker range, around 4 inches. There’s no exact measurement for this.
Our top picks for prostate toys
Sizing for silicone butt plugs
Silicone butt plugs are not really designed for long term wear and focus more on stretching the sphincter muscles. Ranges of insertable lengths will range from a little under 5 inches to around 6 inches. Circumference is different and can begin between 2 and 3 inches and range up to 7 inches to 10 inches.
Because of these sizing differences, you do need to size yourself to make sure you find the right stretch and fuller feeling.
Our top picks for silicone butt plugs
Sizing for tail butt plugs
Tail butt plugs are designed to be worn for extended periods. For this reason, they are generally a little smaller in circumference so they sit comfortably. It is still crucial to know what size the anus is, so measuring the circumference needs to be done.
Most tail plugs come with around 4 to 5 inches for insertable length, and the circumference ranges from 2.5 inches to approximately 4 inches.