Chastity Cage Size Chart & Comparison Guide

Finding the right chastity cage size can feel overwhelming when you're comparing dozens of products with different measurement systems, brand-specific sizing, and conflicting advice. Unlike clothing sizes, there's no universal "small" or "medium" in the chastity world—a Holy Trainer "small" fits very differently from a CB-6000S "small."

This guide provides the comprehensive size charts and comparison tables you need to decode cage dimensions, understand how different brands size their products, and identify which specific measurements matter for your body. Whether you're comparing your first cage options or trying to find a better fit after an unsuccessful purchase, these charts will help you make data-driven decisions.

How to Read a Chastity Cage Size Chart

Chastity cage specifications typically include four to six key measurements, each affecting fit and comfort in different ways. Understanding what these numbers mean—and which ones matter most for your body—is essential before comparing products.

Base Ring Diameter: The inner diameter of the ring that sits behind your testicles and around the base of your shaft. This is measured in millimeters (40mm, 45mm, 50mm, etc.) and is the single most critical measurement for safety and comfort. Too small causes circulation problems and pain; too large allows pull-out and reduces security. Most manufacturers offer rings in 5mm increments from 40mm to 55mm.

Cage Length: The total length of the cage portion, measured from where it connects to the base ring to the tip. This is sometimes called "external length" or "overall length." Standard measurements range from 25mm (nano cages) to 100mm+ (full-size cages). This measurement doesn't need to match your flaccid length exactly—most people size down 10-20mm from their natural flaccid length.

Internal Cage Diameter: The diameter of the tube opening where your penis sits. This typically ranges from 30mm to 45mm. A tighter diameter creates more restriction and prevents movement inside the cage, while a looser fit allows more shifting (which some find more comfortable, others find more frustrating).

Gap Size: The distance between the base ring and the cage entrance. This measurement (typically 5-15mm) determines how much of your shaft base is "captured" between the ring and cage. Too large a gap allows pullout; too small can cause pinching or difficulty achieving full flaccidity.

Cage Diameter/Width: For non-cylindrical cages (like anatomical or flat designs), some manufacturers provide width and height measurements instead of a single diameter. These measurements describe the internal cavity shape.

Understanding Size Categories

The chastity community uses informal size categories that help group products by general fit. While these aren't standardized across brands, they provide useful shorthand for discussing and comparing cages.

Nano/Ultra-Micro (25-35mm length): Designed for extreme size reduction and total flaccid compression. These cages often leave no room for natural flaccid length, forcing everything inward. Popular for humiliation play, feminization, and experienced wearers seeking maximum restriction. Examples include the Nub, Bon4M Morph, and Steelworxx Looker 02. Not recommended for beginners or first-time 24/7 wear.

Micro (35-50mm length): Small cages that significantly reduce visible size without the extreme compression of nano cages. These provide noticeable restriction while remaining manageable for extended wear. Common for experienced users and those specifically seeking a smaller appearance. Examples include the Holy Trainer Nub+, CB-X Mr. Stubb, and many custom metal micro cages.

Small (50-70mm length): The smallest size many manufacturers offer in their standard line. These work well for below-average flaccid length or for anyone sizing down from their natural measurement for increased restriction. This category includes the CB-6000S, Holy Trainer V4 Small, and Evotion Wearable small. A good starting point for many first-time wearers.

Standard/Regular (70-85mm length): The most common size category, fitting average flaccid length with moderate restriction. Most people find this range comfortable for daily wear while still providing effective chastity enforcement. Includes the original CB-6000, Holy Trainer V4 Standard, Cobra 3D Standard. Recommended for beginners uncertain about sizing.

Large/Long (85-100mm+ length): Designed for above-average flaccid length or for wearers who prioritize comfort over restriction. Less common in pre-made cages; often requires custom orders. Some brands like Steelworxx and Mature Metal offer extended lengths up to 120mm.

Base Ring Size Chart

The base ring is your most critical sizing decision. An improperly sized ring causes circulation problems, pain, difficulty urinating, or (if too large) allows escape. Most manufacturers offer rings in 5mm increments, though some premium brands provide 2mm increments for precise fitting.

To find your starting ring size, measure your circumference at the base of your shaft (behind the testicles, where the ring will sit) using our measurement technique. Divide that circumference by 3.14 to get the diameter, then select the closest available ring size. If you're between sizes, start with the larger size and use spacers to adjust fit.

Ring Style Variations: Some cage systems use oval rings, hinged rings, or adjustable designs that don't fit this standard sizing chart. The Steelworxx Anatomical ring system, for example, uses width and height measurements instead of a single diameter. For these specialized rings, follow the manufacturer's specific measurement instructions.

Cage Length Comparison by Category

Cage length determines how much restriction you'll experience and how much your flaccid size will be compressed. This chart organizes common length ranges by category with fit expectations for each.

The "reduction" column shows how much shorter the cage is compared to average natural flaccid length (approximately 75-90mm for most adults). A -20mm reduction means the cage is 20mm shorter than your natural state, requiring compression to fit. This compression is intentional and creates the psychological and physical restriction that makes chastity effective.

Internal Length vs. External Length: Some manufacturers measure cage length internally (the usable space inside) while others measure externally (total cage length). This can create 5-10mm discrepancies between products with identical listed lengths. Always check whether the measurement includes cage wall thickness or describes internal space only.

Popular Cages by Size: Detailed Dimensions

This comprehensive table lists exact dimensions for widely-available cages across all major brands. Use this to compare specific products you're considering or to find alternatives with similar dimensions to a cage you already know fits well.

Reading this table: If you've successfully worn a CB-6000S (54mm length, 32mm diameter) and want more restriction, you might try a Holy Trainer Nub (45mm length, 35mm diameter) for 9mm less length with slightly more room in diameter. Or if the CB-6000S felt too restrictive, a Holy Trainer V4 Small (55mm length, 35mm diameter) offers similar length with more internal space.

Brand-by-Brand Sizing System Comparison

Different manufacturers use completely different sizing philosophies, making cross-brand comparison difficult. Some brands size conservatively (their "small" is actually quite roomy), while others size aggressively (their "standard" is restrictive for many). Understanding each brand's approach helps set appropriate expectations.

CB Series (CB-6000, CB-X): The original chastity cage sizing standard. CB sizes run moderate-to-large compared to modern alternatives. Their "standard" CB-6000 at 74mm was designed for average-to-large builds; many modern users find the CB-6000S (54mm) a better fit. The CB ring system uses fixed sizes in 38mm, 41mm, 44mm, 48mm, and 51mm—decent range but not as granular as some competitors. The polycarbonate material doesn't compress, so these dimensions are absolute.

Holy Trainer: Tends to run small compared to their listed sizes. The Holy Trainer V4 "Standard" at 70mm fits more like other brands' "small." The V5 Nano at 30mm is genuinely extreme—not for beginners. Holy Trainer resin is rigid but slightly warmer than polycarbonate. Their ring sizing (40mm, 45mm, 48mm, 52mm) skips the middle ground between 48-52mm, which can be problematic for people who need 50mm. The integrated lock adds about 5mm to total length.

Evotion Wearable: Sizes run large and comfortable due to the soft silicone material, which compresses and flexes. The "Small" at 65mm fits like a standard/large in rigid materials. Excellent for sleeping and extended wear, but the flexibility reduces the restriction feeling some wearers want. Ring sizes (42mm, 46mm, 50mm, 54mm) work well for most, but the silicone material means you can often go slightly smaller than you'd choose in metal.

Cobra/Kink3D (3D Printed): Highly customizable with sizes available in 1mm increments for both cage and ring. Their "standard" sizing aligns well with CB-6000 dimensions. The 3D-printed nylon has a slightly rough texture that affects perceived fit—a 75mm Cobra feels shorter than a 75mm polished steel cage due to friction. Can specify exact dimensions, making this ideal if you know your measurements precisely.

Cherry Keeper: Another 3D-printed option with exceptional customization. Sizing runs true-to-specification with minimal variance. The integrated lock design means you can't easily swap components. Ring sizes available in 1mm increments from 38-57mm. The headlock design (closed front) creates a different fit dynamic than vented cages—less airflow but often more secure.

Steelworxx (Custom Metal): Uses an anatomical ring system with separate width and height measurements rather than simple diameter. This creates a more precise fit but makes comparison to other brands difficult. Cage lengths and diameters are custom-made to your specifications with extreme precision. Expect 1-2mm variance maximum. Their smallest standard model (Looker 02 at 55mm) is still larger than many micro cages.

Mature Metal (Custom Metal): Fully custom dimensions—you specify exactly what you want. They provide extensive measurement guidance and will recommend sizing based on your measurements. Generally size conservatively (slightly larger than the absolute minimum) for safety and long-term wearability. Lead time is 4-8 weeks, so not ideal for trial-and-error sizing.

Locked In Lust: Premium custom cages sized exactly to customer measurements using a detailed fitting process. Their Crucible model is particularly well-regarded for accurate fit. Sizing runs precise-to-conservative—they'll recommend slightly larger dimensions if your measurements are borderline. Excellent customer service for sizing questions.

Size vs. Material Considerations

The same dimensions feel dramatically different depending on cage material. Understanding how different materials affect perceived fit helps you adjust sizing when switching between material types.

Stainless Steel: Runs the most precise—a 50mm steel cage is exactly 50mm of usable internal space. The smooth, polished surface reduces friction, making the cage feel slightly more spacious than rougher materials at the same size. Steel cages are rigid and unforgiving; there's zero give if you're between sizes. The weight can make the cage feel more restrictive psychologically even if dimensions are identical to a lighter material. Size steel cages to your exact measurements or slightly larger—you can't compensate for too-tight steel the way you can with flexible materials.

Polycarbonate/Resin: Rigid plastic materials (CB series, Holy Trainer) have zero flex but slight variance in manufacturing. Two CB-6000 cages may vary by 1-2mm due to molding tolerances. The material is slightly warmer than metal and has more texture (especially in cheaper models), which can create more friction and perceived tightness. Polycarbonate yellows over time, especially the clear versions, but this doesn't affect fit. Size these materials the same as metal—true-to-measurement or slightly large.

Silicone: The most forgiving material for sizing uncertainties. Silicone compresses, flexes, and stretches slightly, meaning a 65mm silicone cage accommodates a wider range than 65mm in rigid materials. You can often size down 5-10mm from your rigid cage size in silicone for equivalent restriction. The flexibility makes silicone excellent for sleeping and extended wear, but it also means less consistent restriction—movement and bunching inside the cage is more common. Body heat softens silicone slightly, so a cage may feel looser after 30 minutes of wear than when first applied.

3D Printed (Nylon/Resin): Texture and precision vary by printer quality and material. Nylon 3D prints (Cobra, Kink3D) have a slightly rough, matte texture that increases friction—a 70mm 3D nylon cage feels about 5mm shorter than a 70mm polished cage. High-quality resin prints (Cherry Keeper) are smoother and more comparable to injection-molded plastic. 3D printed cages can have slight dimensional variance (±2mm) depending on printer calibration and print orientation. The material is rigid but can have slight flex in thin-walled areas.

Leather: Rare in modern cages but still available in some harness-style designs. Leather stretches significantly with wear and moisture, meaning a cage that fits snugly when new will be noticeably looser after a month of use. Size leather cages smaller than you'd choose in rigid materials, accounting for 10-15% stretch over time. Not recommended for precise sizing needs or long-term 24/7 wear.

When to Size Up or Down

Even with careful measurement and chart comparison, your first cage often isn't a perfect fit. Recognizing the signs that you need to adjust sizing—and knowing which dimension to change—prevents discomfort and helps you dial in your ideal cage.

Signs Your Cage Is Too Small:

• Persistent pain or aching after the first 2-3 days (some initial discomfort is normal during break-in)
• Inability to achieve full flaccidity—you can't fully relax into the cage even after arousal subsides
• Skin bunching or pinching at the cage entrance or tip that doesn't resolve with repositioning
• Difficulty urinating or inability to empty your bladder completely
• Circulation problems (numbness, color changes, cold sensation) that persist beyond the first hour
• Inability to sleep through the night due to discomfort (after a 1-week adjustment period)
• Chafing or raw skin around the cage edges despite proper hygiene and lubrication

Which Dimension to Increase: If pain is at the tip or front of the cage, increase cage length by 5-10mm. If discomfort is at the base or you're experiencing circulation issues, increase ring size by 2-5mm. If you feel squeezed on the sides or top/bottom, you need a larger internal diameter or different cage shape (consider anatomical designs).

Signs Your Cage Is Too Large:

• Ability to pull out of the cage partially or completely, especially when flaccid and cold
• Excessive movement inside the cage—sliding forward and back more than 5-10mm
• The cage slides down and hangs loosely rather than sitting close to your body
• Testicles slip through the ring gap (either one or both)
• You can achieve significant arousal/partial erection without discomfort or restriction
• The ring spins freely around your base when the cage is locked
• You can easily manipulate yourself to orgasm while caged (if prevention is your goal)

Which Dimension to Decrease: If you're pulling out the front or sides, decrease cage length by 5-15mm or reduce internal diameter by 2-5mm. If the ring slips or testicles escape, decrease ring size by 2-5mm. If the entire assembly feels loose and dangles, you likely need both a smaller ring AND shorter cage.

The Goldilocks Zone: A properly sized cage should feel secure and restrictive without causing pain or circulation problems. You should be able to achieve full flaccidity but feel significant resistance during arousal. Movement inside the cage should be minimal (5mm or less of forward/back sliding). The ring should stay in place without spinning freely but not cause numbness or persistent discomfort. You should be able to sleep through the night and wear the cage for 24+ hours without needing removal. Finding this balance usually takes 2-3 sizing attempts for most people.

Using Our Interactive Sizing Tool

While these static charts provide valuable comparison data, our interactive Chastity Cage Sizing Calculator takes your specific measurements and generates personalized product recommendations across all major brands.

The calculator asks for your flaccid length, flaccid girth, base circumference, and wear goals (comfort vs. restriction priority), then cross-references this data against the dimensional specifications of hundreds of products in our database. Instead of manually comparing your measurements to each row in these charts, you'll receive a curated list of 5-10 specific cages most likely to fit your body and preferences.

The tool also accounts for material differences—recommending slightly different dimensions in silicone versus steel based on the flex and compression characteristics explained earlier in this guide. If you've previously owned a cage, you can enter that product name and indicate whether it was too large, too small, or close-but-not-quite, and the calculator will adjust recommendations accordingly.

For users shopping from our recommended cages list, the sizing calculator can confirm whether your measurements fall within the optimal range for any specific product you're considering. This eliminates the guesswork that leads to returns and sizing frustration.