It’s a bit like someone asking a car dealer what type of car should they buy. There are so many factors that to answer the question you do really need to give your office furniture dealer as much information as you can.
You need to think about this question logically, which means starting with factors that you cannot change.
For example the size of the office space and the number of people which have to be fitted into this space. Most office furniture dealers know the minimum square meterage of space, including walkways, which they need to allow per person, so can easily come up with a benchmark size of desk per person.
The next consideration should be what the desks are going to be used for. There is no point specifying a width of 120 cm per desk per person , if each desk is going to have 3 large monitors on it, or if the users need a large amount of under desk storage space. Even a 120 cm wide desk, which seems like an obvious size choice for a call centre or bench desk system, can be too narrow if you try to add a mobile pedestal to it.
By the time you have taken 45 cm away from the desk for the width of the mobile pedestal, and then allowed for 10 cm each side due to the desk leg frames being set inboard of the end of the desk, you are only left with around 65 cm which can be a bit restrictive. Plus invariably nowadays a home for a CPU has also to be found under the desk, which further reduces under desk space.
Then you have to think about what the person using the office desk is like, and what they do. Some occupations require a lot of desk space for reference books and data, or drawings and plans. Others such as administration or accountancy will have ledgers or lever arch files open all the time. And on the other end of the spectrum, many workstations nowadays are almost paperless with the only requirements being a decent sized flat screen, and a keyboard. Plus some people are naturally predisposed to using lots of office desk space whilst a colleague, doing the same job, uses only half.
And not only do you have to think about the width o f the office desk , there is also the depth to consider, although it is much easier now with the almost universal adoption of flat screen monitors.
The old TV like screens were so deep that you had to consider extra deep or radial desks as the only way of ensuring that your staff could move the screens to the required position without them overhanging the desk top. But nowadays, even a 60cm deep desk can comfortably accommodate a medium sized flat screen.
So before deciding what office desk size you must have, speak to an office furniture dealer to see if his experience can help you make the right decision