Dildo Size Guide: How to Choose the Right Length and Girth

Size is the first thing most people look at when they shop for a dildo, and the easiest thing to get wrong. A product name gives you one number, usually the length in inches, but comfort depends far more on how wide the toy is. This dildo size guide explains what the measurements mean, how to work out a size that suits you, and how every dildo in our New Zealand range compares in millimetres and inches.

New to dildos altogether? Our guide on how to use a dildo covers the basics, then come back here to choose a size.

Dildo sizes at a glance

Dildo sizes fall into four broad groups. Pay most attention to the width column, as it has the biggest effect on comfort.

Length, width and girth: what the numbers mean

Three measurements describe a dildo, and listings do not always use the same one.

• Total length is the whole toy from tip to base. This is usually the number in the product name.
• Insertable length is the part you can actually use. On a dildo with balls or a suction base it is shorter than the total length.
• Width, also called diameter, is the distance straight across the shaft at its widest point. Our product pages list it in millimetres, for example 35 x 200mm means 35mm wide and 200mm long.
• Girth strictly means the distance around the shaft. To turn a width into a girth, multiply by 3.14. A 35mm wide dildo is about 110mm around.

Some listings use the word girth when they mean width, so check the unit and the number. If a product name and the listed size ever differ, go by the listed size in millimetres.

Inches to millimetres conversion

NZ shoppers think in centimetres, while dildo names use inches. This table saves the arithmetic.

Why width matters more than length

You control how much of the length you use, so a dildo that is a little longer than you need is rarely a problem. Width is different. You feel the full width from the first moment, and there is no way to use less of it. A change of 5mm in width is far more noticeable than an extra inch of length. When you compare two dildos, look at the width first and treat the length as the second decision.

Weight and firmness also change how a size feels. A heavier dildo feels more substantial in the hand and stays put on a suction base, while a softer material gives a little and can make the same width feel easier.

How to work out your size

1. Start from something you know. If you already own a toy you like, measure across its widest point with a ruler and note the length you actually use. That is your baseline.
2. If this is your first dildo, start small. Around 6 inches long and 35mm wide or less suits most first time buyers. It is easier to move up later than to enjoy something too big.
3. Size up one step at a time. Moving up by about 5mm in width is a comfortable step. Jumping from 35mm to 58mm is not.
4. Match the size to the use. Anal play, strap on play and hands free play each suit different sizes. The sections below cover them.
5. Check the listed size, not just the name. The measurements under Features on each product page are the figures to compare.

Size chart: dildos in our NZ range

These are the single dildos we stock, smallest to largest, with the sizes and weights listed on each product page and current prices.

Two things stand out. The 10.2 inch dildo is longer than the 8 inch but slimmer, so it is the better choice if you want length without extra width. The Huge Dildo is in a class of its own: at 58mm wide it is almost half as wide again as the next widest dildo in the range (40mm), and it weighs more than twice as much. See the full dildos collection for double ended and double penetration styles as well.

What size dildo for a beginner?

Choose the 6 inch dildo. At 34mm wide and 153mm long it is the smallest single dildo we stock, and it is the lightest at 215g. If you would like a little more length at almost the same width, the 7.8 inch dildo is 35mm wide and costs $49.99. Either way, use plenty of water based lube and take your time.

What size for anal play?

Go smaller than you would for vaginal use, and pay attention to width above everything else. Start at 35mm or under, use a generous amount of lube, and only use a dildo with a flared base, balls or a suction base wide enough that the toy cannot travel further than intended. Every dildo in the chart above has a suction base. Move up in small steps over several sessions instead of one. Our anal stretching guide explains how to size up safely.

What size for a strap on?

For strap on play the person receiving sets the size, not the person wearing the harness. A smaller dildo is also easier to control when you are new to it. Two beginner sets come with a short dildo attached: the Strap On Joy Dildo (35 x 100mm, $35.99) and the Strap On Pleasures Dildo and Belt (32 x 110mm, $49.99).

If you would like to choose the dildo yourself, the Strap On Harness ($39.99) comes with a metal ring and a silicone ring and fits our suction base dildos, so you can start with the 6 inch and swap to a larger one later without buying a new harness. The strap on guide covers harness fit and first time tips, and the strap on collection has the ready made bundles.

Large and extra large dildos: 10 inch and 12 inch

Bigger dildos reward a bit of planning.

• Decide whether you want length or width. The 10.2 inch dildo gives you length at a moderate 35mm width. The Huge Dildo is about width and weight: 58mm across and 950g.
• Work up to it. If the widest toy you have used is 35 to 40mm, a 58mm dildo is a big step. Warm up with a smaller toy first and stop if anything is uncomfortable.
• Use more lube than you think you need, and reapply during play. A water based lubricant suits both PVC and TPE toys.
• Use the suction base. A heavy dildo is easier to manage fixed to a smooth, flat surface than held in the hand. Our suction cup dildo guide explains which surfaces work.
• Think about two people. If shared play is the goal, the 15.7 Inch Double Ended Dildo ($59.99) is long because it is designed to be used from both ends, not because one person uses the full length.

Which size should you buy?

Common sizing mistakes

• Buying by length alone. Two dildos of the same length can feel completely different if one is 5mm wider.
• Going too big for a first toy. A dildo that is too large tends to stay in the drawer.
• Forgetting weight. A toy near 1kg handles very differently from one around 200g.
• Skipping lube. The right size with too little lube still feels wrong. See how to choose a lubricant.
• Using a dildo without a wide base for anal play. Always choose a base that stays outside the body.

Frequently asked questions

What is the average dildo size?

There is no official standard. In our range, four of the six single dildos are between 6 and 8 inches long and 34 to 40mm wide, which is a fair picture of a typical mid size.

What size dildo should a beginner buy?

Around 6 inches long and no more than 35mm wide. Our 6 inch dildo measures 34 x 153mm and is the smallest single dildo we stock.

Is girth the same as width?

Not strictly. Width, or diameter, is measured straight across the shaft. Girth is measured around it and is about 3.14 times the width. A 40mm wide dildo has a girth of about 126mm. Some listings use the word girth for width, so check the number.

How do I measure a dildo?

Lay it beside a ruler for length, measuring from the tip to where the base or balls begin for the insertable length. For width, measure straight across the widest part of the shaft. For girth, wrap a soft tape measure around the same point.

Is an 8 inch dildo too big?

For many people it is a comfortable mid size, as you do not have to use the whole length. Check the width before you decide. Our 8 inch dildo is 40mm wide, which is 5mm wider than the 7.8 inch and 10.2 inch models.

How big is a 12 inch dildo in centimetres?

Twelve inches is 30.5cm. Dildos sold in this size class are as much about width as length. The largest in our range is listed at 58mm wide and 270mm long, and weighs 950g.

Shop dildos by size in NZ

Playmate Adult Store is proud to call New Zealand home, and orders are sent in discreet packaging. Compare every size in the dildos collection, add a water based lube and a toy cleaner to the same order, and start with the size that suits you now. You can always move up later.