Quarter-millimetres (Q) to Millimetres
Type a value in Quarter-millimetres (Q) and get the result in Millimetres, calculated exactly.
16 Quarter-millimetres (Q) = 4 Millimetres
Precision
Exact factorThis result is exact.
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Formula
mm = Q × 0.25
To convert Quarter-millimetres (Q) to Millimetres, multiply the value by 0.25.
Worked examples
- 1 Q × 0.25 = 0.25 mm
- 16 Q × 0.25 = 4 mm
- 100 Q × 0.25 = 25 mm
This factor is exact by definition.
Conversion table
| Quarter-millimetres (Q) | Millimetres (mm) |
|---|---|
| 1 | 0.25 |
| 2 | 0.5 |
| 4 | 1 |
| 8 | 2 |
| 10 | 2.5 |
| 12 | 3 |
| 14 | 3.5 |
| 16 | 4 |
| 18 | 4.5 |
| 20 | 5 |
| 24 | 6 |
| 32 | 8 |
| 36 | 9 |
| 48 | 12 |
| 64 | 16 |
| 72 | 18 |
| 96 | 24 |
Values marked ≈ are rounded; the rest are exact.
Reverse table: Millimetres to Quarter-millimetres (Q)
| Millimetres (mm) | Quarter-millimetres (Q) |
|---|---|
| 1 | 4 |
| 2 | 8 |
| 4 | 16 |
| 8 | 32 |
| 10 | 40 |
| 12 | 48 |
| 14 | 56 |
| 16 | 64 |
| 18 | 72 |
| 20 | 80 |
| 24 | 96 |
| 32 | 128 |
| 36 | 144 |
| 48 | 192 |
| 64 | 256 |
| 72 | 288 |
| 96 | 384 |
Unit definitions
- Quarter-millimetres (Q) Q
- Exactly 0.25 millimetres, used for type sizes in Japan.
- Millimetres mm
- One thousandth of a metre; 25.4 mm make an inch.
Questions people ask
Quarter-millimetres (Q) to Millimetres: what is the conversion factor?
One Q is 0.25 mm.
How do I convert Quarter-millimetres (Q) to Millimetres?
Use the formula above. For example, 16 Q = 4 mm.
Is the conversion exact?
Yes. Both units have exact definitions, so the factor is exact; a result is only rounded when its decimals never end.
Factors checked 19 October 2026.