They are the same volume — the number never changes
A millilitre and a cubic centimetre are two names for one volume, so "converting" mL to cc means copying the number across. This is deliberate, not luck: a litre was fixed as 1,000 cm³, which makes a millilitre exactly one cm³.
So why two names at all
- cc came first. Medicine and engineering settled on cubic centimetres long before mL was standardised, so the older term stuck in those fields.
- Syringes carry both. A "5 mL" and a "5 cc" syringe are the same syringe; the two labels sit on identical graduation lines so anyone can read it.
- Engine cc. A 600 cc motorbike or a 1,000 cc engine is stating cylinder volume in cubic centimetres — 600 cc is 600 mL is 0.6 litres.
Stepping up to litres
The only real conversion nearby is to litres, since 1,000 of either unit make a litre.
| mL | cc | Litres |
|---|---|---|
| 10 mL | 10 cc | 0.01 L |
| 100 mL | 100 cc | 0.1 L |
| 500 mL | 500 cc | 0.5 L |
| 1,000 mL | 1,000 cc | 1 L |
Common questions
Is 1 mL exactly 1 cc?
Yes, exactly. A millilitre and a cubic centimetre are the same volume by definition, not a close approximation. There is no conversion factor: the number never changes.
Why do syringes and engines still say cc if mL is the standard?
Habit and history. Medicine and the motor trade adopted cc decades before mL became the SI-preferred spelling, so a 600 cc motorbike and a 5 cc syringe keep the old label. Modern syringes print both on the same marks.
How do I convert 500 mL to cc?
You do not need to. 500 mL is 500 cc. Whatever number you have in one unit is the identical number in the other.
