Office size is a sum before it is a standard: the desks the headcount needs at the ratio the attendance supports, times the area each desk position gets, plus the meeting and support space, plus the circulation, and the office square footage is what that adds up to. Searches for a standard office size, a standard office size for one person or the typical office size want a number from an authority, and the honest answer is that office sizes are the organisation's own allowances added together, with one external reference on this hub that binds federal agencies and nobody else. This guide is the sum on this site's worked example, what each term in it is, and how the free worksheet works your own version of it with no account.
The desks, and the area each gets
120 people at 7 desks per 10 is 84 desk positions; at 60 square feet each, the workstation plus its share of the aisle, that is 5,040 square feet of desk area. The ratio is the attendance's decision and the area per desk is the organisation's or its designer's; neither is a standard this worksheet applies. A standard office size for one person, in the sense people search for it, is that second figure, and 60 is the worked example rather than a recommendation.
The shared space and the circulation
Add 1,800 square feet of meeting and collaboration space and 1,500 of support, reception, kitchen, storage, print and plant, and the net area is 8,340 square feet. Add 25% for circulation, the corridors and the space between things, and the office square footage is 10,425 square feet, 86.9 per person at that headcount. Change the ratio to a desk each and the same allowances give 14,265 square feet, 118.9 a person; the typical office size is whichever the organisation's own decisions produce.
The one external reference, and whose rule it is
The U.S. General Services Administration sets a design requirement of 150 usable square feet per person for federal office space, leased or federal, except public-facing areas (GSA USE IT Act reporting guidelines, read 2026-09-05). It binds federal agencies and nobody else, and it is quoted here as a reference point outside the worked example rather than as a standard office size this worksheet applies to yours. Your own ratio, area per desk and allowances are the guidelines the worksheet works from.
Working your own office sizes
The office space per person worksheet on this site takes six inputs, headcount, desk ratio, area per desk, meeting space, support space and circulation, and returns the desks, the desk area, the net area, the total and the square feet per person, on the page with no account. Run it per team and the sum across teams is the floor; run it at two ratios and the difference is what desk sharing is worth in square feet. HardFM Pro saves every worksheet against the building and keeps the inventory the figures sit on.
Questions people ask about office size
What is a standard office size per person?
There is no single standard this worksheet applies; office size is the organisation's own desk ratio, area per desk and allowances added together. The one external reference on this hub is the U.S. General Services Administration's 150 usable square feet per person design requirement, which binds federal agencies only.
What is the typical office size for 120 people?
On the worked example, 10,425 square feet: 84 desks at 7 per 10 and 60 square feet each, 1,800 square feet of meeting space, 1,500 of support and 25% circulation. At a desk each the same allowances give 14,265. Your own inputs give your own figure.
How do I work out office square footage?
Desks from headcount and ratio, desk area from desks and area per desk, plus meeting and support space, plus circulation as a percentage. The free office space per person worksheet does the sum from six inputs with no account.