Party Budget Calculator
Build a full party budget from per-guest costs plus fixed venue and decor spending.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
Separate per-guest costs from fixed event costs to see how each input affects the estimate. Enter your own local prices; this calculator does not provide market rates or recommend a spending level.
Worked example
calculated with the default values below
Number of guests 40 · Food per guest 18 $ · Drinks per guest 10 $ · Rentals per guest 4 $ · Decorations 120 $ · Venue hire 400 $ · Entertainment 250 $ Food 720.00 $ · Drinks 400.00 $ · Rentals 160.00 $ · Decor, venue and entertainment 770.00 $ · Total budget 2,050.00 $ · Cost per guest 51.25 $ · Share that scales with guests 62.4 %
General background references
Disclaimer
These calculators give general estimates. Sizing, pricing, availability and standards vary by brand, retailer and country, so treat the output as a starting point and confirm it against the seller's or authority's own figures.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
T = G (f + d + r) + F0; T_g = T ÷ G; p_v = G (f + d + r) ÷ T × 100
- G
- Number of guests
- f
- Food cost per guest
- d
- Drinks cost per guest
- r
- Rental cost per guest
- F0
- Fixed costs (decor + venue + entertainment)
- T_g,p_v
- Total per guest; variable-cost share (%)
All amounts share the chosen currency; the variable percentage is the share of per-guest costs within the total.
Frequently asked questions
Why does trimming the guest list cut the budget when fixed costs stay put?
Food, drinks and rentals scale with guests while decor, venue and entertainment are fixed, so at 40 guests the variable part is $1,280 of a $2,050 total, about 62%. Drop to 30 guests and the variable side falls to $960 while the $770 fixed cost is unchanged, saving $320 with no change to the event itself. The per-guest figure, about $51 here, is the clearest place those savings show.