Solution concentration calculator
Per cent by mass, mass per volume and parts per million.
Fill in the fields and the result will appear here automatically.
Choose mass fraction or solute mass per volume of finished solution. The first mode reports mass percent and mass-based ppm; the second reports grams per 100 mL, written as % w/v, and g/L. Solvent mass or solvent volume must not replace the total solution quantity.
How it works
Formula and logic
w/w: 100 × solute mass/solution mass; ppm: 10⁶ × the same mass ratio. w/v: 100 × m/V with m in g and V in mL gives g per 100 mL; 1000 × m/V gives g/L. The solute-mass limit applies only to w/w. Solute mass must be finite and nonnegative; solution mass and volume must be finite and positive. Unrepresentable results produce an error; small results are displayed without rounding to zero.
Example
25 g in 500 g of solution gives 5.00% by mass, 50,000 ppm and 475 g of solvent. 3 g in 100 mL of finished solution gives 3.00% w/v and 30 g/L.
Fields and units
- Form of concentration — list option
- Mass of substance, g — g
- Mass of solution, g — g
- Volume of solution, mL — mL
How to use
- — Choose mass fraction or mass per volume.
- — Enter the dissolved substance mass in grams.
- — Enter total solution mass in grams or final solution volume in millilitres.
Method and limitations
- Calculation method
- Formula and logic
- Data or methodology source
- IUPAC: mass fraction — component mass relative to total mixture mass IUPAC: mass concentration — component mass per mixture volume
- Limitation
- Mass fraction and mass concentration are calculated; volume fraction and solubility are not. ppm is mass-based. Machine arithmetic and displayed values are rounded.
FAQ
Why enter solution mass rather than solvent mass?
The solute is part of the total. For 25 g of solute and 475 g of solvent, enter 500 g of solution. The solvent difference is reported separately.
What does the mass-per-volume percentage mean?
Grams of substance per 100 mL of solution, not volume fraction. Comparing it with mass percent requires the solution density.
Can the result exceed 100%?
Mass fraction cannot exceed 100% because a component cannot exceed the total mass. There is no universal 100 limit for g per 100 mL; solubility is not checked.
Does ppm equal mg/L?
Here ppm means mg per kg of solution, a mass ratio. Equality with mg/L requires a density of 1 kg/L, which is not assumed.
Can the solute mass be zero?
Yes. With positive solution mass or volume, 0 g of solute gives 0% and respectively 0 ppm or 0 g/L. Losing a positive concentration to zero during calculation produces an error.