Guide for roasters
Calculating roast needs: how many kilos will you roast tomorrow?
Roast need is the amount of roasted coffee required for tomorrow's deliveries that is not yet on the shelf. It is worked out from four figures: orders, delivery dates, finished coffee stock and roast loss. This guide walks through the calculation with an example, and at the end explains how Haimoo Flow does the same automatically.
Haimoo Company Oy · Published 1 November 2026 · Reading time about 5 minutes
1. Which orders belong in tomorrow's roast?
The starting point is simple: an order is roasted on the day before delivery. If the coffee leaves on Thursday, it is roasted on Wednesday. Tomorrow's roast list therefore holds every order whose delivery date is the day after tomorrow.
Two exceptions are easily forgotten. Late orders, whose delivery date has already passed, are roasted first. And orders with no agreed delivery date are worth including straight away, because they do not surface on their own.
2. Bags into kilos
Orders arrive as a mix of bags and kilos. Roast need is always calculated in kilos, so each line is converted according to its bag size. Six 250-gram bags are 1.5 kg. Ten one-kilo bags are 10 kg. Grind does not affect the kilos, but it does affect packing, so it is worth recording on the line.
The calculation is done coffee by coffee. If three customers order the same coffee, their kilos are added together, and the roast list has one line.
3. Deduct finished coffee
If the same coffee roasted yesterday is still on the shelf, it is not roasted again. The finished coffee balance is deducted from the need. If the same roasted coffee is sold as two products, for example as bags and in bulk, the balance is shared between them and must not be deducted twice.
When the roast list covers several days, it is worth using stock for the orders with the earliest delivery date first. Then the most urgent order is sure to leave, and later ones are roasted fresh.
4. From roasted to green coffee
Green coffee goes into the roaster, and you need more of it than comes out roasted. Roast loss is typically 12–20 percent. The green coffee need is calculated by dividing the roasted need by (1 − loss):
green coffee = roasted need ÷ (1 − loss)
Example: 14.5 kg of roasted Rituaali at 16.5 percent loss is 14.5 ÷ 0.835 = 17.4 kg of green coffee.
If the roaster's batch size is, for example, 10 kg of green coffee, 17.4 kg is split into two batches. The number of batches tells you how many roasts the day holds and how long it will take.
5. Order from light to dark
Roast order is not a calculation, but it is worth deciding at the same time. Light roasts first and dark ones last: the drum heats up over the day, and after a dark roast a light one does not turn out the same way. Within the same roast level, the earliest delivery goes first.
Example: one roast day
| Coffee | Ordered | Ready | To roast | Green (16.5% loss) |
|---|---|---|---|---|
| Rituaali, medium | 10 × 1 kg + 4 × 1 kg + 20 × 250 g = 19 kg | 4.5 kg | 14.5 kg | 17.4 kg, 2 batches |
| Party Mokka, dark | 8 × 1 kg + 2 × 1 kg = 10 kg | 0 kg | 10 kg | 12 kg, 2 batches |
| Kenya Gatuya AA, light | 12 × 250 g + 6 × 250 g = 4.5 kg | 0 kg | 4.5 kg | 5.4 kg, 1 batch |
| Total | 33.5 kg | 4.5 kg | 29 kg | 34.8 kg, 5 batches |
The figures in this example are made up. Order: Kenya first (light), then Rituaali, Party Mokka last.
Most common mistakes
- Late orders get forgotten. Yesterday's delivery that did not leave does not appear on tomorrow's list unless it is counted separately.
- Bags are counted as pieces. 20 bags can be 5 kg or 20 kg. Always convert to kilos before adding up.
- Finished coffee is deducted twice when the same coffee is in two products.
- Loss is left out, and too little green coffee is weighed. The difference is 15–20 percent.
- The calculation is redone in the evening when an order arrives late. If the calculation is in a spreadsheet, every new order is a new calculation.
How Haimoo Flow does this
Flow calculates roast needs with the same rules, but directly from orders. The delivery date determines the roast day, and late orders and those with no date are always on today's list. Bags are converted to kilos according to bag size, and finished coffee in Stock is deducted for the orders with the earliest delivery date first. Once roast loss and batch size are entered in Settings, each line shows the green coffee quantity and batches, and the roast order runs from light to dark.
When a line is checked as roasted, its orders move to packing. The Dashboard shows the same calculation for the whole week too. Read more about Roast needs or see who Flow is for.
Questions about the calculation
All questionsWhat is roast loss?
Roast loss is the share of weight coffee loses in roasting as water evaporates and the chaff comes off. Typical loss is 12–20 percent depending on the roast level and the coffee. The green coffee need is the roasted need divided by (1 − loss).
Should finished coffee be deducted?
If the same coffee is still on the shelf, yes. Otherwise you roast it twice. Deduct only coffee whose roast date is fresh enough for the customer.
How does Flow calculate this?
The same way: the delivery date determines the roast day, bags are converted to kilos, finished coffee is deducted from stock, loss is entered in Settings and the batch size splits the coffee into batches. The figures come from orders, not from estimates.