The King Rings Sizing Process is a multi-step fitting system developed specifically for our heavy tungsten carbide C-Rings and glans rings. Because precision-sized metal rings require real-world experimentation rather than simple self-measurement, proper fit is determined through a process of assessment, testing, and discovery. This guide explains how the sizing system works, helps you determine whether King Rings are appropriate for you, and prepares you for the fitting journey ahead. Whether you are new to rings or an experienced wearer, we recommend beginning with our sizing rings rather than relying on measurements, estimates, or other rings you already own.

Why Our Process Is Different

Sizing matters.

Metal rings are rigid, heavy, and precision-sized. Unlike silicone or flexible materials, there is no “close enough.” The right fit can feel incredible. The wrong fit can be disappointing or uncomfortable.

Most online sellers reduce sizing to only a tape measurement.

We go much further.

It’s actually fun and a great way to engage a partner.

The measure and calculate method is prone to error but – importantly – inconsistent. How much “squeeze” should be applied when measuring? Or maybe none at all? Do you measure flaccid or hard or both? There is so much variance, it makes a very poor metric.

Over the years, we have also found that desired fit depends on more than simple circumference:

  • anatomy
  • intended use
  • ring width
  • experience level
  • comfort preference
  • and even confidence

Two men with identical measurements may prefer entirely different fits.

That is why our process is built around experimentation and discovery rather than simple self-measurement.

The King Rings Sizing Process

You will:

  • confirm your approximate size range (jump to it)
  • acquire a sizing kit by mail
  • identify your ideal fit through actual wear
  • apply your $75 credit toward your first metal ring

Guesswork is risky. Confidence matters.

Precision fit is part of what makes King Rings feel substantial, secure, and luxurious – but it also means careful sizing is essential.

Plastic as a proxy lets you explore the actual dimensions of our heavy metal rings without the investment.

Our sizing process eliminates guesswork by allowing you to compare multiple sizes in real-world conditions before investing in a heavy metal ring.

Do Not Skip Our Sizing Process

Experience with metal rings from other sellers is not a reliable metric for guessing your fit here. We offer finer sizing than you’ll find elsewhere, along with highly unique bands that are both wide and heavy.

We want you to succeed! And we believe in this time-tested product and process so much that we offer a financial incentive to start with a set of Sizing Rings.

You will end up with:

✅ Confidence in your size
A $75 store credit

Why The Sizing Rings Work

  • Dimensionally matched to our finished metal rings
  • Multiple sizes for real-world comparison
  • Designed for fully functional performance testing – not guesswork
  • Safe experimentation through lower-limit testing
  • Engineered breakaway feature for peace of mind

When used correctly, the sizing process is highly accurate and allows you to purchase your metal ring with confidence.

Sizing Rings

Our Sizing Rings are 3D printed in-house with plant based PLA plastic. – from renewable natural sources – and are completely body safe. In fact, PLA plastics like ours are used to manufacture medical implants designed to dissolve in the body.

Safety is our focus at every step.

PRECISION FIT

Designed for heavy metal rings where small differences matter.

FOOLPROOF

Begin with Sizing Rings before purchasing a finished metal ring.

King Rings Standard Sizing Rings Set

Is The King Rings Size Range Appropriate for You?

Our rings fit the vast majority of men, but this quick check helps confirm you are within our supported size range before getting started. The measure and calculate method is common in the C-ring market, it’s where most sellers’ advice ends. Here, it’s where ours begins.

Get Your Measure

At a time when you are warm, flaccid, and the boys are loose, collect rough measurements.

FOR C-RINGS: Using a string, ribbon, or tailor tape, wrap it around the base of your penis behind your scrotum. This should be a gentle wrap, firmly against your skin but not squeezing flesh into any wrinkles.

FOR GLANS RINGS: These rings fit on the shaft of the penis, just behind the head (glans), and are held in place by their grip behind the ridge (corona) of the head. That’s where to measure.

FOR BOTH TYPES: Mark the overlap, straighten out the ribbon, and measure the distance between your two marks.

FOR C-RINGS: You are safely within our C-ring size range if you measure between:

✅ 16.5 cm to 22.8 cm or
✅ 6 1/2 in. to 9 in.

FOR GLANS RINGS: You are safely within our glans ring size range if you measure between:

✅ 8.8 cm to 13 cm or
✅ 3 1/2 in. to 5 1/8 in.

How Does the Math Work?

The great thing is, you don’t really need to know. But if you are curious, our best-guess equation includes a 20% squish factor. So if your measurement was 20 cm (200mm) the equation looks like this: (200mm x 0.8) / 3.14 = 51mm. Is this your ideal size? Maybe. Should you trust it enough to invest in a lifetime accessory? Absolutely not. It’s only an estimate.

What To Expect from the Kit

Cock and Glans Sizing Kit

Our sizing kit ships with a standard range of sizes from:

22mm – 32mm (glans rings) and
42mm – 56mm (C-rings).

There is one additional size available on request, if you are at the upper end of our range please request a 58mm sizer at checkout.

In addition, the sizing kit includes a finger ring sizing tool, a printed sizing guide, and other useful information. See the Sizing Rings product page for full details.

Shipping in the US is free and you’ll also have access to expedited shipping at checkout, if you prefer.

Step 1

Order Your Sizing Kit

Start here and get a full sizing kit discretely shipped to your door.

Step 2

Follow The Fitting Guide

After your sizing rings arrive, follow our step-by-step guide to find your ideal fit.

What Happens After Sizing?

The sizing process is the foundation of the King Rings experience. Once your size is confirmed, purchasing a metal ring becomes straightforward.

Your $75 sizing credit is applied toward your first ring purchase, leaving only one decision left; choosing a style.

Whether you prefer polished tungsten, black PVD, rose gold, faceted finishes, or something more understated, you can shop confidently knowing the fit question has already been answered.

Still Have Questions?

Why We Use Sizing Rings

Informed Investment

Our sizing rings exist because tungsten carbide rings are expensive precision objects, and proper fit cannot reliably be determined from measurements alone.

The sizing process allows customers to experiment safely and make informed decisions before purchasing a finished metal ring.

It is not the fastest way to sell rings.

But after years in this business, we believe it is the best way to help customers succeed.

Why King Rings Remains Direct-To-Consumer

Available Exclusively Here

We produce our own line of products and do not sell to distributors, retail outlets, or other vendors. This is an intentional choice to keep our focus on service.

Proper sizing requires:

  • education
  • experimentation
  • guidance
  • and customer support

Those things are difficult to provide from a retail shelf.

By remaining direct-to-consumer, we are also able to avoid the layered markups associated with traditional retail distribution. This helps keep pricing aligned with practical value rather than retail overhead.

By remaining direct-to-consumer, we are able to focus on:

  • broader sizing availability
  • customer guidance
  • educational resources
  • and continuous refinement of the products themselves

In other words, we can focus on helping customers find the right fit rather than simply making a sale.

Sizing Process FAQ

The measure and calculate method promoted elsewhere is prone to error but – importantly – even when it’s done right, all you end up with is a good guess.

An estimate may be all you need if the sizes available are limited. Meaning, if you had to choose between 1.5 inch, 2 inch and 2.5 inch, a calculated ring size estimate of 1.9 inches may be all you need. Two of the three options are obviously no good.

King Rings sizes differ by 2mm (about 1/16th inch), the width of a grain of rice. This affords opportunity to really dial in a perfect fit and the only practical way to discover your ideal size is through experimentation with fully functional rings in an assortment of sizes.

It’s about precision. We craft highly precise tools for performance and pleasure, and we provide a sizing process which is equally precise. There is no room for guess work.

If you are experienced with rings of this type then you are at an advantage, you will approach the sizing process with greater confidence but you should not skip it. Three main reasons:

  1. The rings you have were the most appropriate sizes available at the store where you purchased them. Maybe there was a little compromise in that choice, you had to pick the “closest” ring to your self-measure. What if your ideal fit were just slightly smaller, how would you know unless you try?
  2. The width of King Rings bands tend to make them fit more snug than thinner bands with the same inside diameter. They also compress a larger volume of tissue, which allows them to do the same work without having to be as tight. Using a standard steel donut ring as a reference point for size selection may disappoint you.
  3. Money saved. We are so confident in the value of our sizing process that we offer a financial incentive to start your King Rings journey with a set of sizing rings. We give you the entire investment back plus a little extra spending money in the form of a store credit.

The “Three Finger Rule of Thumb” is primarily a safety check before things get hard. Some gentlemen get nervous about becoming trapped in a ring and this technique allows you to estimate probable outcome before committing to the erection.

Fingers are a blunt tool and vary in size among individuals. This is NOT a stand-alone sizing technique but can shortcut you to the appropriate size range for performance testing – which is key to success.

It is not enough to assess fit without becoming erect in a ring. You need to experiment to know how well a ring performs for you during playtime. You want a ring that provides a gentle but persistent boost without being overly restrictive.

For more detail on selecting the right size, see “How do I know which size is right for me?” below.

Maybe. But this is insufficient to justify an investment.

The plastic sizing rings are a very poor proxy for casual wear of our heavy metal rings but they perfectly mimic the constrictive nature. This is why we emphasize the importance of performance testing.

Find the size which is wrong for you. Seriously, that’s the trick.

Use the “Three Finger Rule of Thumb” to work your way down to a 2 finger fit – then switch to performance testing (becoming erect in the ring). If the ring does not produce a purple throbbing monster, then move down a size and repeat.

You are looking for the ring which is too small for comfort when erect. By this we mean; excessive discoloration, a dull ache, or anything that robs you of pleasure. You want to pay attention to the erection itself, not how the plastic feels against your skin. This is your too-small size, it may be suitable for casual only wear but is a poor choice for playtime.

It is VERY unlikely you would become trapped in a sizing ring but – admittedly – we are suggesting you push the boundary. For this reason, our rings are engineered with a breakaway feature to alleviate any fear of entrapment. A quick twist with needle nose pliers and you’re out.

Your ideal metal ring size is one size up from the too-small size. So if your wiener got angry in a 48mm then your go to size is 50mm.

Can you wear the ring all day? Yes. Will is slip? Maybe, but it is your best option for a single ring and we can offer tips to mitigate slip.

Some gentlemen with multiple rings step down to the too-small size for casual wear only.

For example, your preferred size for extended sessions with your partner is a 50mm; it fits great, is very comfortable, and gives your erection a gentle but persistent boost without being overly aggressive. You can comfortably wear a 50mm ring casually all day, but it is prone to slip some, especially on hot days.

One size down, 48mm, may stay put much better when worn casually and when your partner surprises you with unexpected attention, the 48mm will do its job very well – a little too well – and so you limit your activity to a “quicky”. You won’t get trapped in a 48mm, it is just pretty uncomfortable after 10 minutes fully erect.

Note that you should always always always fully vet ring sizes in breakaway plastic sizing rings before slipping into metal. Your judgement, your result, be safe.

Start With The Right Foundation

Whether you are completely new to metal rings or refining a fit you already understand, our sizing system exists to help you make informed decisions with confidence.

Order Your Sizing Kit

Start here and get a full sizing kit discretely shipped to your door.