A busy hour built from two orders
A week-by-hour heatmap is the fastest way to see when a kitchen actually trades. It is also the fastest way to draw a confident conclusion from two orders and a coincidence.
The grid everybody wants: days down the side, hours across the top, colour for how good each cell is. Seven by twenty-four, one glance, and you can see your week.
It is genuinely the most useful single report a food kitchen has. It answers staffing, it answers opening hours, and it answers the argument about whether Tuesday is worth it. We built ours this week. Most of the work was not the drawing.
168 cells, and most kitchens do not fill them
A single-unit kitchen open six days might trade in forty of those cells. The rest are not bad hours. They are hours the shutter was down.
Draw a zero there and the grid becomes mostly a picture of your opening times, with the actual trade squeezed into a narrow band of colour you can no longer read. Worse, the empty cells drag the scale: everything real looks good by comparison, because it is being compared to closed.
So an empty cell in ours is drawn as empty. Not zero — nothing. It takes no part in the colour scale and no part in the best-and-worst list.
The cell that is worse than empty
Average order value is the number people act on. It is also the number that falls apart on small counts.
Two orders on a Tuesday at 3pm, one of them a big group booking, and that cell shows an average of forty pounds. On a heatmap it is the brightest square on the grid. Somebody looks at it and staffs Tuesday afternoons.
It is not a finding. It is one large order and a coincidence, and next Tuesday it will not be there.
Ours refuses to compute an average from fewer than three orders. Those cells are marked thin and are excluded from the shortlist of best and worst hours — they are still drawn, because "we traded here, barely" is information, but they are not allowed to become a recommendation.
Compared with what
The other half is the comparison. Show a week against the previous week and every cell gets a percentage, including the ones that went from nothing to something. Nothing to something is not "up 100%" — it is an hour you opened. Ours says opened and closed rather than inventing a number for a change from zero.
Two things to check on any heatmap you are shown
Ask what an empty cell means, and ask how few orders a cell can have before it stops being shown as a rate. If the answer to the first is "zero" and the answer to the second is "one", you are looking at a picture of your opening hours with some noise painted on it — and the brightest square is probably a party.