Q factor
By Marji · Updated · Sources and editorial policy
Also called: quotient factor
The Q factor is a fixed allowance added to every plate cost to cover items too small or too shared to cost individually — cooking oil, butter, seasoning, condiments, complimentary bread. Set it as a flat amount per cover or a percentage of plate cost, sized from what those items actually cost you rather than from a borrowed figure.
Sizing it from real data
Q factor per cover = Monthly spend on uncosted items ÷ Monthly covers
Measured spend divided by covers; a guessed allowance can be wrong in either direction.
Worked example · A 1,900-cover month
- Cooking oil
- $410
- Butter (non-recipe)
- $285
- Salt, pepper, dry seasoning
- $140
- Condiments + ramekins of sauce
- $220
- Bread service
- $560
- Total uncosted
- $1,615
- Covers
- 1,900
- Q factor per cover
- $0.85
The bread service is the largest line; without it the allowance would be $0.56 a cover. That is the point of measuring rather than assuming.
Two refinements worth making: apply a different Q factor to dishes that genuinely differ (a $6 side does not consume the bread service), and re-derive it annually. A Q factor set in 2023 has missed three years of price changes.
Run the numbers
Recipe cost calculator
The guide that works it through
Recipe Costing, Step by Step: Purchase Unit to Served Portion
Cost a recipe from supplier pack to served portion, with source dates, measured yields, a worked plate and explicit handling of missing ingredient costs.