How to Choose the Right Size and Firmness for Your First Silicone Dildo
Picking your first dildo can feel… a little overwhelming. So many shapes, sizes, and materials — and then you see words like “shore hardness” and “dual-density” and think, okay, I just wanted something that feels good.
The good news: once you understand size and firmness, choosing the right silicone dildo gets much easier.
In this guide, we’ll walk through everything you need to know before you buy (or design!) your first one.
Why Silicone Is a Smart Choice for Beginners
Before we talk size and firmness, a quick note on material.
High-quality silicone is:
Non-porous – it doesn’t soak up fluids, so it’s easier to clean and more hygienic
Body-safe – it’s free of phthalates and other common irritants found in some cheap toys
Durable – it holds its shape and texture for years with proper care
Versatile – it can be made soft, firm, matte, glossy, smooth, or textured
That means you can focus on getting the right feel instead of worrying about safety.
Step 1: Choosing the Right Size
When we talk about dildo size, we’re usually talking about:
Length (often “insertable length”)
Girth (circumference around the widest part)
Both matter — but girth usually makes the biggest difference in how a toy feels.
A. Length: How Long Is “Too Long”?
For a first dildo, you don’t need to chase impressive numbers. Your body is unique, but a good beginner range is usually:
Insertable length: about 12–16 cm (4.75–6.5 inches)
Longer toys aren’t “wrong,” but they:
Take more practice and control
Can feel uncomfortable if you push past your natural limits
Are simply not necessary for good sensations, especially at the beginning
If you’re unsure, start in the middle of that range. You can always size up later.
B. Girth: The Most Important Measurement
If you only pay attention to one number, make it circumference (girth).
Most people will feel a big difference between, for example, 3.5 cm and 4 cm diameter, even if the length is the same.
For beginners, a comfortable girth range is often:
Slim/Beginner: 9–10.5 cm (3.5–4.1 inches) circumference
Average: 11–12.5 cm (4.3–4.9 inches) circumference
If you’re used to inserting nothing or only small items (like slim fingers or small plugs), start on the slimmer end. If you’re already comfortable with moderate insertion, average might be perfect.
Tip:
Roll a measuring tape into a loop and test different circumferences around your fingers to visualize how it might feel.
Step 2: Understanding Firmness
Silicone firmness is often measured on a Shore scale (typically Shore A for toys). You don’t need to memorize the exact numbers, but it helps to understand the basic categories:
Soft / Plush: squishy, bends easily
Medium: flexible but with some “push back”
Firm: holds shape strongly, less bend
Some toys are also dual-density – a soft outer layer with a firmer core to mimic body tissue.
Picking the Right Softness for Silicone Adult Products
How Firmness Changes the Experience
Softer silicone
Feels gentler and more “forgiving”
Great for beginners, sensitive bodies, and deeper thrusting
Less intense pressure on sensitive areas
Medium silicone
A balance between squish and structure
Good for thrusting and pressure without feeling too hard
Very popular as an “all-rounder” firmness
Firm silicone
Excellent for targeted pressure (e.g., G-spot, A-spot, prostate)
Easier to control and position
Can feel intense or too hard for some beginners
For a first dildo, most people do best with soft to medium firmness — especially if you’re still learning what your body likes.
Step 3: Matching Size + Firmness to Your Body & Preferences
Now let’s put it together. Ask yourself:
How experienced am I with insertion?
Totally new → slim girth, medium or softer
Some experience → average girth, medium
Very experienced and likes fullness → you might enjoy a thicker toy, but consider starting with a medium firmness first.
Do I want gentle comfort or strong pressure?
Gentle, relaxing, or longer sessions → softer, slightly slimmer toy
Strong, focused pressure on specific spots → medium to firm toy, not too long
Am I mainly interested in thrusting or more static pressure?
Thrusting → a bit of flexibility is good; choose soft to medium
Static pressure or grinding → medium to firm can work better
Step 4: Other Design Details That Matter
Size and firmness are key, but a few extra design features will also shape your experience:
Shape: Straight for versatility, curves for G-spot/prostate focus
Base: A wider base adds safety for anal play and can be harness-compatible
Surface: Smooth silicone is beginner-friendly; ridges and textures are better once you know what you like
Weight: Heavier toys can feel more “present”; lighter toys are easier to maneuver
If you’re working with a manufacturer (like us) who offers customization, you can fine-tune all of these to suit your body and preferences.
Step 5: Start Smaller, Upgrade Later
Your first silicone dildo doesn’t have to be your forever dildo. Think of it as a starting point:
Begin with a comfortable, confidence-boosting size and medium or soft firmness
Learn what your body likes – more girth, less length, more curve, more firmness, etc.
Use that experience to choose or design your next toy (maybe a custom one!)
Your comfort matters more than the numbers on a product page. If you choose something that feels good for you, you picked the right size.
Hi, I am the author of this article. For the past 10 years or so, we have been dedicated to meeting the custom silicone product needs of our customers from over 50 countries and regions around the world.
If you have any questions, please contact us for a free, no-obligation quote.
