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Free event planning calculators.
The numbers every room needs before anything gets drawn: how many fit, how big the stage has to be, how much floor the dancing takes, what linen the tables need, and what size tent holds the lot. Each one runs the same arithmetic the EventDiagram editor runs, so the answer you get here is the answer you get on the plan.
Seating chart maker
Paste a guest list, set the seats per table, and get a chart that keeps families and groups together — and names any party it had to split, rather than splitting them quietly. Runs in your browser; the list never leaves it.
Room capacity calculator
How many people fit in a room at banquet, theater, classroom or cabaret — worked from real table footprints and wall aisles, with the capacity-chart figure alongside so you can see the difference.
Stage size calculator
How big a stage a speaker, a panel, a DJ or a five-piece band needs, in whole 4′×8′ decks — plus the deck height the back row needs to see over and what the ceiling will allow.
Dance floor size calculator
What size dance floor a guest count needs, sized per dancer rather than per guest, with the panel count to order in both 3ft and 4ft grids and the room it really occupies.
Tablecloth size calculator
The linen every table takes at every drop, rectangles and rounds — plus the reverse lookup, because the question is usually “what does this cloth fit?” with the cloth already in the van.
Tent size calculator
What size tent a guest count needs once the dance floor, buffet, bar and head table are under it too — which is what turns a 30×60 into a 40×60.
Why these give different answers to the last calculator you used
A number you can put on a drawing
Most event calculators divide an area by a figure and hand back a total. That is fine as a sanity check and it is why venue capacity charts exist. It also cannot tell you that your room is 4ft too narrow for a fourth column of tables, that a 72″ round packs worse than a 60″ in your particular width, or that the stage you just sized will not leave headroom in a 9ft breakout room.
These work the other way round. They start from the footprint of a real object — a table with its ring of pulled-back chairs, a 4ft by 8ft stage deck, a 3ft dance floor panel — and fit whole objects into a real room. The answers come back as things you can order and place: nine decks, forty-nine panels, four rows of six. Where a rule of thumb disagrees, both numbers are shown, because the gap between them is usually the decision somebody needs to make.
When you want to go further than a number, the free plan draws the room to scale, auto-fills the setup, puts the stage and floor in, and walks it in 3D. No credit card, and pricing starts at $9 a month if you need more than one diagram at a time.
Draw the room, not just the number
Everything these calculators work out, placed to scale in a plan you can send to a client or a crew.
No credit card required