OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. In the first example the result is -0.8.
The calculator is not FRAX and not a bone-density result. OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note.
Enter data and click Calculate.
The calculator uses the numbers you enter. OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. In the first example the result is -0.8.
The five form fields are Age, Body weight, Prior low-trauma fracture, Years since bone-density screening, and Vitamin D + calcium habit quality. OSTA means: This is the main result on this page. In the first example it is -0.8. Age means: The first form field. It enters the formula or sits beside the result. OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. Body weight means: The second form field. The calculator is not FRAX and not a bone-density result.
The second example gives 1.8. The third example gives -4.8. OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. In the first example the result is -0.8.
The calculator is not FRAX and not a bone-density result.
Enter 62, 58, 0, 3, 6, then click Calculate. A comma in 12.5 is read the same way as a period. Fields on a 0-10 scale are notes and are not the primary result unless this page formula says so.
OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note.
In the first example the result is -0.8. OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note.
-0.8
OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. In the first example the result is -0.8.
1.8
OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. In the second example the result is 1.8.
-4.8
OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. In the third example the result is -4.8.
In the first example the result is -0.8. OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note.
With the second set of fields the result is 1.8.
With the third set of fields the result is -4.8.
OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note.
The calculator is not FRAX and not a bone-density result.
This is the main result on this page. In the first example it is -0.8. The first form field. It enters the formula or sits beside the result. OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. The second form field. The calculator is not FRAX and not a bone-density result.
Yes. 12.5 and 12,5 are read the same way.
No. Fields on a 0-10 scale are notes, unless this page formula counts marked items from them. The primary result comes from this page formula.
(Weight in kilograms minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number.
No. Years since DEXA are a note. The calculator is not a bone-density test.
The page has only five fields. OSTA without sex stays an approximation; the copy says so.
OSTA is positive when weight in kg is greater than age, and negative when age is greater. In the first example the result is -0.8.
No. The fracture flag sits in the second row. OSTA stays (weight in kg minus age) × 0.2.
OSTA is (weight in kg minus age) × 0.2. Sex is not a field, so this is a rough index. A prior fracture sits beside that number. Years since DEXA are a note. The calculator is not FRAX and not a bone-density result.
Page updated in 2026.
