Dart Intake Calculator
The 20 cm between a 96 cm bust and a 76 cm waist is what the darts have to swallow. Four of them — two front, two back — take 5 cm each, and because a dart opens either side of its centre line, each leg is drawn 2.5 cm out. That 2.5 cm is the line you actually mark on the pattern.
Your numbers
Intake per dart
5cm
Half-intake per leg
2.5cm
Difference
20cm
Formula
Intake per dart = (Larger circumference − Smaller circumference) ÷ Darts
Splitting 20 cm four ways does not mean four equal darts. The side with more curve takes more, so 6 cm at the front and 4 cm at the back is the usual sort of split. Once a single dart passes about 4 cm its point bubbles, and the fix is two smaller darts side by side.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Larger circumference (cm)The larger measurement, such as the bust, taken on the body rather than the pattern. | 96 | 1 and up |
| Smaller circumference (cm)The smaller measurement, such as the waist, taken in the same posture. | 76 | 0 and up |
| DartsHow many darts share the difference, front and back together. | 4 | 1 and up |
Step by step
Quick reference table
Results when only Larger circumference (cm) changes and everything else stays put.
| Larger circumference (cm) | Intake per dart (cm) | Half-intake per leg (cm) | Difference (cm) |
|---|---|---|---|
| 48 | 0 | 0 | 0 |
| 72 | 0 | 0 | 0 |
| 96 | 5 | 2.5 | 20 |
| 144 | 17 | 8.5 | 68 |
| 192 | 29 | 14.5 | 116 |
What each result means
| Result | At default values |
|---|---|
| Intake per dart (cm)The width one dart removes, both legs added together. | 5 |
| Half-intake per leg (cm)How far one leg opens from the dart's centre line — the line you mark. | 2.5 |
| Difference (cm)The gap between two values — a quantity, not a rate. | 20 |
Common mistakes
Splitting 20 cm four ways does not mean four equal darts. The side with more curve takes more, so 6 cm at the front and 4 cm at the back is the usual sort of split. Once a single dart passes about 4 cm its point bubbles, and the fix is two smaller darts side by side.
Glossary
- Larger circumference
- The larger measurement, such as the bust, taken on the body rather than the pattern.
- Smaller circumference
- The smaller measurement, such as the waist, taken in the same posture.
- Darts
- How many darts share the difference, front and back together.
- Intake per dart
- The width one dart removes, both legs added together.
- Half-intake per leg
- How far one leg opens from the dart's centre line — the line you mark.
- Difference
- The gap between two values — a quantity, not a rate.
Frequently asked questions
Q. How is Dart Intake Calculator calculated?
Intake per dart = (Larger circumference − Smaller circumference) ÷ Darts — The 20 cm between a 96 cm bust and a 76 cm waist is what the darts have to swallow. Four of them — two front, two back — take 5 cm each, and because a dart opens either side of its centre line, each leg is drawn 2.5 cm out. That 2.5 cm is the line you actually mark on the pattern.
Q. Can you walk through an example?
With Larger circumference 96cm, Smaller circumference 76cm, Darts 4, the answer is Intake per dart 5cm.
Q. What do I need to enter?
Enter Larger circumference, Smaller circumference, Darts. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Larger circumference (cm) moves the answer to Larger circumference (cm) 48 → Intake per dart (cm) 0 and Larger circumference (cm) 192 → Intake per dart (cm) 29. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
Splitting 20 cm four ways does not mean four equal darts. The side with more curve takes more, so 6 cm at the front and 4 cm at the back is the usual sort of split. Once a single dart passes about 4 cm its point bubbles, and the fix is two smaller darts side by side.
Related calculators
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