Urn Sizing Guide

Urn sizing guide with a cloudy background

Choosing the perfect urn for a loved one's ashes takes careful consideration. You need to decide on the right material, colour and design to pay fitting tribute to their memory. Once you have found the perfect urn design, you then need to choose the right size to ensure it can accommodate the ashes. At Eternal Urns we strive to provide the most diverse and accessible range to our customers, and that begins with understanding what size you need.

This urn sizing guide will help you choose the right size urn and explain some of the different options available to you. 

Understanding Cremains

The cremation process is a process in which the body is incinerated in a cremation chamber, leaving only the cherished ashes, also referred to as cremains, behind. Cremains consist of bone fragments and other non-combustible materials and it is these that are kept in the urn to memorialise your departed loved one. The amount of cremains generated depends on factors such as size of the body, bone density and the cremation process itself but the cremains of an adult typically weigh between 1.8 and 3.6 kilograms.

Calculating Urn Size

The size of an urn is typically determined by its volume, which is measured in millilitres. 

A general rule of thumb for urn sizing is that one kilogram of body weight will yield approximately 38 millilitres of cremains. Therefore, a person weighing 75 kilograms will typically require an urn with a capacity of 2,850 millilitres or more. However, it is usually advisable to choose an urn that is slightly larger than the calculated size to ensure there is ample space for the cremains.

To calculate the urn size needed, simply follow these steps:

  1. Determine the deceased's approximate weight before cremation.
  2. Convert the weight to millilitres (1 kilogram = 38 millilitres).
  3. Add a buffer of 10-20% to account for variations in the cremation process and ensure the urn is large enough.

For example, if the deceased weighed 75 kilograms as in the example above, the best way to calculate the minimum urn size required is:

  • 75 kilograms x 38 millilitres = 2,850 millilitres
  • 2,850 millilitres x 1.1 (for an additional 10% capacity) =  3,135 millilitres

In this case, an urn with a volume of around 3,200 millilitres should be ample for the ashes.

How to Choose the Right Size Urn

Choosing the right size urn depends on if you plan on storing the full amount of cremains, partly scattering them or dividing them amongst family. It is important to note, however, that the above calculations are if you want to store the full cremains. It is also important to know that the exact amount of cremation ashes recieved will differ due to multiple factors, contact your local crematorium or funeral home for exact details. After consulting our guide on ashes youll expect to recieve, you can see below the type of sizes youll need to consider if you want to hold the full or partial amount of cremains. If you happen to buy an urn that is smaller than required, there is no harm in scattering the extra remains. Make sure to consult your local laws and regulations regarding this practice as they may differ from state to state. 

Keepsake Urns 

These small urns hold a portion of the cremains, typically up to 150 millilitres. Keepsake urns are ideal for family members who wish to share the ashes or keep a small memorial in their homes.

Small Urns

Small urns are designed for children or small adults and can hold between 500 millilitres to 1.5 litres of cremains.

Medium Urns 

Suitable for smaller adults, medium urns can accommodate between 1.5 and 2.2 litres of cremains.

Large Urns

Suitable for most adults, large urns can accommodate up to 3.4 litres of cremains.

Companion Urns 

Intended for two individuals, companion urns can hold between 6 and 12 litres of cremains depending on the design. These urns are ideal for couples who wish to be memorialised together.

Extra Large Urns

Extra large urns are for individuals with larger cremains or those who want to include personal items or multiple people in the urn. They can hold up to 7 litres of cremains depending on the design.

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Scattering Tubes

Scattering Tubes

If you are unable to find an urn that meets your sizing requirements or you have found the perfect urn but have an excess of ash, you can consider scattering. Scattering the remains of your loved one can be a very touching send off and help greatly with obtaining a sense of closure. Biodegradable scattering tubes are available to purchase on our store and are a great option in dealing with excess cremains. 

Custom Urns

Custom Urns are another option with those who are in need of a larger receptacle. Many artisans and urn manufacturers offer customisation options, allowing you to choose the size, material, and design that best suits your needs. Custom urns may take longer to create and may be more expensive than standard urns, but they can provide a one of a kind tribute to your loved one. If you are in need of a custom urn, you can browse our range of customisation options or alternatively contact us at orders@eternalurns.com.au to discuss other alternatives.

Cremation Jewellery

Three pieces of cremation jewellery

One beautiful alternative to an urn is a piece of cremation jewellery. These collections include stunningly designed pendants, rings and lockets which can hold a small amount of cremains. Cremation jewellery allows you to keep your loved one with you at all times and wear something that acts as a constant reminder of your happy memories.

Final Thoughts

We hope this urn sizing guide will help you to choose the perfect-sized urn for your loved one. Whether you are looking to keep all their ashes in a place of prominence in your home or wear a little memory of them around your neck or on your finger, choosing the right urn is crucial. By calculating their weight and the volume of the cremains you will be able to select an urn that is practical, meaningful and truly beautiful.