Scale a 1:4 mixing ratio
Multiply both sides of 1:4 by the batch multiplier you need. A quarter batch is 0.25 and 1, a half batch is 0.5 and 2, two batches are 2 and 8, and the combined amount is always five times the multiplier.
Equivalent ratio table
| 1 | 0.25 | 0.25 | 1 |
| 2 | 0.5 | 0.5 | 2 |
| 3 | 0.75 | 0.75 | 3 |
| 4 | 1 | 1 | 4 |
| 5 | 1.25 | 1.25 | 5 |
| 6 | 1.5 | 1.5 | 6 |
| 7 | 1.75 | 1.75 | 7 |
| 8 | 2 | 2 | 8 |
| 9 | 2.25 | 2.25 | 9 |
| 10 | 2.5 | 2.5 | 10 |
| 11 | 2.75 | 2.75 | 11 |
| 12 | 3 | 3 | 12 |
| 13 | 3.25 | 3.25 | 13 |
| 14 | 3.5 | 3.5 | 14 |
| 15 | 3.75 | 3.75 | 15 |
| 16 | 4 | 4 | 16 |
The ratio names parts, not percentages: one plus four makes five total parts.
The first material is 20% of the combined amount and the second is 80%.
A 0.25 multiplier preserves the ratio even though both quantities are fractional.
How it works
The formula
multiplier[row] = start + (row - 1) x step
firstQuantity[row] = firstPart x multiplier[row]
secondQuantity[row] = secondPart x multiplier[row]
To simplify decimal parts:
write both parts as base-10 integers over powers of ten
cross-multiply to one common denominator
divide both resulting integers by their greatest common divisor
The same multiplier is always applied to both parts.
What it assumes
- Both base parts and both multiplier controls are positive. A zero-part relationship can be written, but it does not make a useful scale table and is refused here.
- Parts are dimensionless until the visitor assigns a unit. A row can mean grams, litres, pixels or people only when both columns are interpreted consistently.
- The simplified headline is exact for the decimal spelling accepted by the number control. Table quantities use JavaScript numbers and are shortened to twelve significant digits to remove binary display tails.
- A ratio names quantities alongside each other. A ratio of 1:4 contains five total parts; it does not mean one part out of four total.
Common questions
Does 1:4 mean one part plus four parts or one part in four total?
In ratio notation it means one part alongside four parts, so there are five total parts. One part in four total would instead split as 1:3.
How much total mixture does a 1:4 row make?
Add the two columns. At multiplier m, the row is m and 4m, so the combined amount is 5m in the same unit.
Sources
The full method, worked example and every assumption behind this figure are on Ratio Table Maker.