Most salons know what they spend on colour a month and what they charge for a colour service, but have never put the two numbers next to each other. This does that, using only figures you already have. Nothing is stored and there is no form to fill in.
Cost per head is your monthly colour spend times twelve, divided by your colour heads times fifty-two. That is arithmetic on two figures you already have. There is no industry average hidden in it and nothing to disagree with.
It is also, for most owners, the first time they have seen the number at all.
Colour cost as a share of the colour price is the number to watch over time. If it climbs, either your product costs went up or your mixing did, and those need very different responses. Many owners aim to keep it under about a tenth of the service price, though what counts as healthy varies with how much of your work is long or blonde.
One caution: this is an average across every head. That average is exactly what hides the problem, because a root touch-up and a full head of balayage are averaged into the same figure. Seeing the spread, not the average, is what changes decisions.
We have deliberately not pre-filled it with a number we could defend, because we would be guessing about your salon. What we can say is where the waste sits: in what gets mixed and not used. Overmixing is rational behaviour when you cannot see the cost — nobody wants to run out halfway through a head with foils in, so everyone rounds up, every time, and the rounding is never measured.
Set that slider to whatever you would genuinely believe, including zero. The point of the row is to show you the size of the prize, not to claim it.
Weigh every bowl for one week. That is enough to see the shape of it: which services are underpriced, which shades get over-poured, and how big the gap is between what was mixed and what went on the head. ColorLab does the weighing and costing as part of the service so nobody has to stop and write anything down, but the week of weighing is worth doing whatever you use to do it.