The Insider: Get on the case for the best laptop protection

The beauty of a laptop is that you can use it anywhere, but carrying one around regularly can place a strain on your back and shoulders – some weigh in at more than 2kg. While most people invest time in choosing the right laptop, they often just use the carry case that comes with it, which might not be the best option for their needs.

If you rarely take your laptop outside your home, for the odd excursion you could simply slip it into a pillowcase to prevent scratching, or a soft "sleeve" if you have a netbook, and then put it into a normal bag. But if you regularly carry a heavy laptop, you should get a good laptop bag to protect yourself and your computer.

There's a wide choice of styles available, including shoulder bags, backpacks and suitcase-style bags. You should be prepared to spend between £30 and £50 for a good-quality bag if you plan to use it regularly, but the type you choose will probably depend on the laptop you have, how and where you use it, and how you travel.

"Shoulder bags come in a range of trendy styles and can be easy to carry, but think about how the weight is distributed to prevent straining your back, and never buy a bag without adjustable straps," says Matt Bath, technology editor at Which? Computing. "Experts say you should place the strap across your body to balance weight across your spine, or if you opt for a briefcase-style bag, try to carry a second bag in your other hand rather than putting everything in the laptop bag."

Backpacks are sturdier as they have two adjustable straps which go over the shoulders, and some have straps that go around the waist to support the even distribution of the bag's weight on your back. They're also a good option if you're concerned about personal safety, as they don't obviously contain a laptop.

Suitcase-style wheeled laptop bags and pilot cases are best if you travel frequently, or carry a heavy load. Some are "airport check-in-friendly" and may mean you don't have to remove the laptop from its bag in US airports.

Where to buy

You can buy on the high street in stores such as PC World or at luggage retailers, but you might find that the styles and colour ranges are limited. The largest selection is online, but try on different styles of bag before you buy, to make sure that your chosen style feels comfortable for your frame and size. For example, cyclist-style bags can feel awkward and uncomfortable on some female frames.

It's also difficult to get a good idea of what the material will look and feel like if you buy online.

Questions to ask...

What size is it?

Bags are categorised by the size of your laptop's screen, not by the bag's dimensions. So if your laptop has a 17in screen, look for a 17in laptop bag, or 8.9in for a netbook.

Does it adequately protect your laptop?

The bag should be padded across the bottom and have straps to make sure that the laptop isn't going to slide about too much inside – or fall right out of it if the bag is dropped.

How much does it weigh?

Check the weight of the bag itself and add your laptop's weight, plus extra for the additional items you'll carry at the same time. Leather bags look smart but weigh more than man-made materials.

Is it weather-proof?

If you're going to be outside regularly, make sure the material and the bag are waterproof, not just water-resistant.

The Insider is written by Which?, the independent consumer champion. For more information go to . To get three issues of 'Which?' magazine for a special price of £3, call 01992 822800 and quote INADVICE.