Storage Unit Size Calculator: How to Choose the Right Storage Unit

Picking the right unit is easier than you might expect. In this self storage size guide, we’ll show you how to choose the right space for your needs and how to use our self storage unit size calculator. If you’re new to self storage, you’ll also find helpful tips on storage options, pricing, and location.

Storage Calculator

Calculate Your Storage Needs with Our Storage Calculator

Whether you’re storing personal belongings or business items, the amount of space you need will vary. At Attic Self Storage, we offer a wide range of self storage unit sizes, so you can choose a space that fits your needs — without paying for more than you use.

Our storage size calculator makes it easy to find the right unit in just a few clicks, helping you choose with confidence.

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Double wardrobe

Small car

10-15

These are just some examples from the range of sizes we have available. View by location to see the full range.

10 ft2 unit

We recommend a: SqFt | SqM

10 ft2 unit

Ideal for storing the contents of a small car or the equivalent of a double wardrobe.

These are just some examples from the range of sizes we have available. View by location to see the full range.

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How Big of a Storage Unit Do I Need?

Our self storage space calculator helps you estimate the amount of storage space you need today, but before you book, take a moment to consider a few key details:

  • The type of items you plan to store
  • Whether you’re storing for business and may need more space in the future

Next, use the storage unit size chart below to compare your options. It shows the unit sizes we offer, what each one is best for, and what may not fit, helping you choose the right unit first time.

Storage Unit Size Chart

Best For Storing

Best For Storing

Not Suitable For

10 sq ft

A few boxes, suitcases, seasonal items

Furniture or large bulky items

15 sq ft

Boxes, compact personal items, small shelving

Beds, sofas

20 sq ft

Decluttering a small room, office boxes

Large furniture pieces

25 sq ft

Content of a small studio area, chairs, boxes

Beds with mattresses

35 sq ft

Studio flat contents, small sofa, mattress, boxes

Beds with mattresses

50 sq ft

Typical 1-bed flat contents

Full house contents

60 sq ft

Large 1-bed or compact 2-bed flat

Bulky multi-room storage

75 sq ft

Standard 2-bed home contents

Large family home storage

100 sq ft

2-3 bed home contents or a single garage, larger furniture

4-bed house content

125 sq ft

3-4 bed house contents

Extensive commercial quantities

150 sq ft

Large home storage or combined household items

Archive-scale or bulk stock

200 sq ft

Substantial home storage or growing business stock

High-volume stock storage

300 sq ft

Large business storage or long-term household storage

Warehouse-level quantities

500 sq ft

Extensive business storage or major home clearances

Industrial-scale storage needs

Our 3-Step Guide to Using the Storage Unit Size Calculator

To make things easier, we’ve created a storage space calculator to help you work out which storage unit size best suits your storage needs — whether you’re storing a few items or the contents of a 3-bedroom house. Just follow the three simple steps below to get a clear idea of the space you’ll need before choosing your unit.

Step 1: Use the Storage Space Calculator Slider to Check Out the Range of Sizes

Start by using the space size slider to get a rough idea of how much storage space you’ll need. Simply move the slider until it matches the amount of space your items would usually take up at home. To help you picture this, the calculator compares your items to familiar spaces, such as:

  • A wardrobe or double wardrobe
  • A full kitchen or small garden shed
  • A studio or one–two bedroom flat
  • A two or three-bedroom house
  • A single or double garage
  • Larger homes, up to a four or five-bedroom house

Step 2: See What Your Chosen Space Can Hold

Alongside your selected unit size, we show easy, everyday comparisons — such as vehicle size and the number of storage boxes it can hold — to help you get a better feel for the space.

For example, a 10 sq ft unit is roughly the size of a double wardrobe and can hold the contents of a small car, or around 10–15 standard-sized boxes.

Step 3: Get a Quote for Your Selected Storage Unit Size

Once you’re happy with the space you’ve chosen, you’ll see the storage unit size we recommend. Units are shown in square feet (sq ft), with square metres (sq m) included for reference.

When you’re ready, you can get an instant quote by entering your postcode to check availability and pricing for your chosen unit at any of our nine London locations.

We hope our self storage unit size guide is helpful to you. When it comes to choosing a storage unit with us, you’re not alone. We’re on hand to help you along every step of the journey. With multiple stores across the city, our friendly teams can help you get the right storage solution for you.