Free planning tool

Conference room size calculator

Enter a room size to see how many people it seats, or enter a headcount to see how big the room needs to be. Pick the seating layout and watch the room redraw.

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Square feet or metres
Seven layouts

Boardroom layout10 seats shown

Your room

Room area

sq ft

Usable floor area inside the walls. A 15 by 20 ft room is 300 sq ft.

Seating layout

Email my room estimate

Receive your current seating estimate, layout and a link to revisit the calculator.

Measure the usable floor

Inside the walls, minus anything fixed: a credenza, a screen wall, a wide door swing.

Pick the layout

The same room seats three times as many people in theatre rows as around one boardroom table.

Check it against code

Fire and accessibility rules set the hard ceiling. Use the result as a planning figure, then confirm with your local code.

Space per seat by layout

Common planning allowances for a comfortable seat, including circulation space. The calculator uses the midpoint of each range.

Layout	Per seat (sq ft)	Per seat (m²)	Typical use
Theatre	8 to 10	0.75 to 0.95	Town halls, presentations, no note-taking
Round tables	10 to 12	0.95 to 1.1	Workshops in groups, events with catering
Classroom	15 to 20	1.4 to 1.9	Training with laptops, exams
Huddle	20 to 25	1.9 to 2.3	Two to six people, quick calls
Boardroom	25 to 30	2.3 to 2.8	Decision meetings, one shared table
U-shape	30 to 35	2.8 to 3.3	Facilitated sessions with a presenter
Hollow square	30 to 35	2.8 to 3.3	Committee meetings, everyone faces in

There is no single legal figure: fire regulations, accessibility requirements and the actual furniture set the real limit, so treat the result as a planning figure and check it against your local code.

Conference room size chart

Seated capacity by room size for the three layouts people ask about most. Capacities use the midpoint allowance and round down.

Room size	Boardroom	Classroom	Theatre	Example dimensions
100 sq ft (9 m²)	3 to 4	5	10	10 by 10 ft
150 sq ft (14 m²) huddle	5	8	16	10 by 15 ft
200 sq ft (19 m²)	7	11	22	12 by 17 ft
300 sq ft (28 m²) 10 people	10	17	33	15 by 20 ft
400 sq ft (37 m²)	14	22	44	20 by 20 ft
600 sq ft (56 m²)	21	34	66	20 by 30 ft
800 sq ft (74 m²)	28	45	88	20 by 40 ft
1,000 sq ft (93 m²)	35	57	111	25 by 40 ft

A long narrow room seats fewer people at a boardroom table than a square room of the same area, because the table has to fit first.

Questions about conference room size

How is conference room capacity calculated?

Divide the usable floor area by the space each seat needs in the layout you have chosen. A boardroom seat needs more room than a theatre seat, because the table, the chair and the space to push the chair back all count. Round down, then subtract anything that eats floor area: a credenza, a screen cart, a wide door swing. The glossary entry on conference room capacity covers the terms.

How big is a 150 sq ft room?

About 14 square metres, roughly 10 by 15 feet. As a meeting room it seats five or six around a table, eight in classroom rows, and up to about sixteen in theatre style with no tables. It is the classic huddle room size.

What size conference room do I need for 10 people?

Around 250 to 300 sq ft (23 to 28 m²) for a boardroom table, or 150 to 200 sq ft in classroom rows. Add space if the room hosts video calls, since people spread out to stay in shot, and if you expect laptops, papers and coffee on the table.

What are the right conference room dimensions and table size?

A rule that works in practice: allow about 30 inches (75 cm) of table edge per person, and keep at least 3 feet (90 cm) between the table edge and the wall so people can get in and out. A 10-seat boardroom table is therefore around 12 feet long, and the room around it needs to be at least 18 feet long. The meeting room layout entry explains the layouts used above.

Why is the number on the door often wrong?

Rooms get relabelled when furniture changes and nobody updates the sign, so a room booked for twelve turns out to seat eight. Booking data fixes this. When people book a room for a stated headcount and then check in, you can see which rooms are booked over their real capacity and which large rooms host two-person calls. That is the job of meeting room booking software, and the reason capacity is a field on every room in it. More free tools live in the HybridHero Hub.

See all HybridHero FAQs

From capacity to bookings

Rooms booked by real headcount

HybridHero shows the right-sized room first, releases no-shows automatically and reports which rooms are over or under their capacity, so the number on the door finally matches how the room is used.

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Free tool. No sign-up needed to use the calculator.