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Chastity Cage
Sizing Tool

3 measurements. Your ideal cage length, diameter, and ring size — so you buy right the first time.

1
Length
2
Girth
3
Ring Size

Step 1 of 3

Flaccid Length

Base to tip, pressed against pubic bone

3.00"
76mm
1.00"6.00"
Tip

Measure at room temperature when fully relaxed. Cold causes temporary shrinkage.

How to Measure for a Chastity Cage (Step by Step)

You need three numbers: flaccid length, flaccid circumference, and base ring circumference. Take all measurements when fully flaccid and at room temperature — cold and warm conditions change size significantly.

Flaccid length: Measure from the tip of the glans to the base where the shaft meets the body. Press a ruler flat against the pubic bone and measure straight. Note this in inches.

Flaccid circumference: Wrap a soft tape measure around the widest part of the shaft. This is usually just behind the glans. Note the full circumference in inches.

Base ring circumference: Wrap the tape around the base — behind both the shaft and scrotum, where the ring will sit. This is the most critical measurement for safety.

What Size Chastity Cage Do I Need?

The universal sizing rule: your cage tube should be 0.25 to 0.5 inches shorter than your flaccid length. This gentle compression is what keeps the cage secure and prevents slippage without causing pain. Too long and it won't contain erections. Too short and it pinches.

Tube diameter should match your flaccid circumference divided by 3.14 (π). If your circumference is 3.5 inches, your ideal inner diameter is about 1.1 inches (28mm). Most cages list inner diameter — not outer — so double-check when comparing specs.

If you're between sizes, go slightly larger on diameter and slightly smaller on length. Comfort during extended wear matters more than precise confinement.

Chastity Cage Ring Size Guide

The base ring is the most safety-critical part of any chastity cage. Standard ring sizes are 35, 38, 40, 43, 45, 48, 50, 53, and 55mm. Divide your base circumference (in mm) by 3.14 to get your ring diameter, then round to the nearest standard size.

When between two sizes, always choose the larger ring. A too-tight ring cuts off circulation and can cause serious injury within hours. Signs of too-tight ring: numbness, color change, cold skin. Remove immediately if any of these occur.

Many starter cages come with 2-3 ring sizes included. If you're buying your first cage, look for kits that include multiple rings so you can find your fit without buying multiple products.

Chastity Cage Size Chart by Category

Sizing needs vary significantly by body type. The tool above calculates your personal dimensions, but here's a general reference:

  • SCage 1.5–2.0" · Diameter 1.0–1.1" · Ring 38–40mm
  • MCage 2.0–2.5" · Diameter 1.1–1.25" · Ring 43–45mm
  • LCage 2.5–3.0" · Diameter 1.25–1.4" · Ring 48–50mm
  • XLCage 3.0–3.5" · Diameter 1.4–1.6" · Ring 50–55mm

These are starting points. Use this tool for your exact measurements — average sizing categories are notoriously inconsistent across brands.

Silicone vs Metal vs Resin: How Material Affects Fit

Silicone cages flex, which means you can go 0.1–0.2 inches shorter and slightly narrower than your baseline measurement. The material conforms to your body, making it more forgiving for first-time wearers. Easier to clean, comfortable for 24/7 wear, but less visually striking.

Metal cages (stainless steel or zinc alloy) are rigid and completely unforgiving. Match your measurements as precisely as possible. Metal is heavier, more durable, easier to keep hygienic, and the standard for long-term chastity. Popular metal cages include the CB-6000 in metal variants and various Chinese steel designs.

Resin and 3D-printed cages are generally true to their listed dimensions with minimal flex. Custom 3D-printed options from makers like Kink3D allow you to input exact measurements — ideal if you fall outside standard sizing ranges.

Common Sizing Mistakes (and How to Avoid Them)

Measuring erect instead of flaccid is the most common mistake. Cage sizing is always based on flaccid measurements. An erect measurement will result in a cage that is painful to wear and impossible to put on.

Choosing too small a ring to feel more secure. The ring should feel snug but you should be able to slide a finger underneath. Constriction is dangerous. Discomfort that builds over hours means the ring is too small.

Ignoring urethral alignment when choosing tube diameter. If the tube is too narrow for your diameter, the urethra opening won't align with the cage tip — this creates hygiene problems and discomfort. Check that the cage opening position matches the listed specs.

Found a cage you like? Use the AI Fit Check to paste the product URL and verify dimensions against your measurements before buying.

FAQ: Chastity Cage Sizing Questions

How do I measure for a chastity cage?+
Measure flaccid length (tip to base), flaccid circumference (widest part of shaft), and base ring circumference (behind shaft and scrotum). Take all measurements relaxed and at room temperature.
What if my measurements fall between standard sizes?+
For the tube: go shorter (0.25" less than flaccid). For the ring: always go larger when between sizes — a too-tight ring is a safety risk. Many cages come with multiple ring sizes included.
Can I use this tool for the CB-6000 or Holy Trainer?+
Yes. This tool gives you universal body measurements. Once you have them, use our Fit Check to paste any product URL — including CB-6000, Holy Trainer, Bon4, or any other brand — and get a compatibility score.
Is it normal for sizing to feel different day to day?+
Yes. Temperature, hydration, and arousal state all affect flaccid size. Measure multiple times across different days and take the average. Most people find their size varies by 0.25–0.5 inches.
Are my measurements stored or shared?+
No. All calculations run in your browser. Measurements can optionally be saved to your device's local storage to auto-fill the Fit Check tool — they never leave your device.