Calculator
Plotly Graph
This chart shows the identity relationship between percent w/w and g/100g. Every valid value falls on the same diagonal line.
Example Data Table
The table below uses a 250 g total sample mass to show how the same concentration translates into actual solute mass.
| Percent w/w | g/100g | Solute in 250 g Sample (g) | Solvent in 250 g Sample (g) | Equivalent ppm |
|---|---|---|---|---|
| 0.5 % | 0.5 g/100g | 1.25 | 248.75 | 5,000 |
| 1.0 % | 1.0 g/100g | 2.50 | 247.50 | 10,000 |
| 2.5 % | 2.5 g/100g | 6.25 | 243.75 | 25,000 |
| 5.0 % | 5.0 g/100g | 12.50 | 237.50 | 50,000 |
| 12.5 % | 12.5 g/100g | 31.25 | 218.75 | 125,000 |
| 25.0 % | 25.0 g/100g | 62.50 | 187.50 | 250,000 |
| 40.0 % | 40.0 g/100g | 100.00 | 150.00 | 400,000 |
Formula Used
1) Percent w/w Formula
% w/w = (mass of solute ÷ total mass of mixture) × 100
2) g/100g Formula
g/100g = (mass of solute ÷ total mass of mixture) × 100
3) Direct Conversion Rule
Percent w/w = g/100g
4) Actual Solute Mass in a Sample
Solute mass = total sample mass × (percent w/w ÷ 100)
How to Use This Calculator
- Select the conversion direction.
- Enter the concentration value.
- Enter the total sample mass in grams.
- Choose the number of decimal places.
- Click Convert Now to see the result above the form.
- Use the export buttons to download the result as CSV or PDF.
FAQs
1) What does percent w/w mean?
Percent w/w means grams of solute in every 100 grams of total mixture. It is a mass-based concentration unit used in chemistry, food work, manufacturing, and formulation.
2) Why is percent w/w the same as g/100g?
They use the same basis. One percent w/w literally means 1 gram of solute in 100 grams of mixture, so the numeric value is identical.
3) Can the value be greater than 100?
For a normal mixture definition, no. A component cannot exceed the total mixture mass, so percent w/w and g/100g should stay between 0 and 100.
4) Is percent w/w the same as percent w/v?
No. Percent w/w uses mass over total mass. Percent w/v uses mass over solution volume. They are different units and should not be interchanged directly.
5) Why does this calculator ask for total sample mass?
Total sample mass helps estimate actual grams of solute and solvent in a real batch. That makes the result more useful for mixing, scaling, and checking compositions.
6) Can I use this for food and recipe work?
Yes. Mass-based concentration is common in food, flavoring, brines, and ingredient blends. Just keep all inputs in consistent mass units.
7) How is ppm calculated from percent w/w?
First convert percent to mass fraction by dividing by 100. Then multiply that fraction by 1,000,000 to get ppm on a mass basis.
8) When should I round the result?
Round only to the precision your process needs. Lab calculations may need more decimals, while production sheets and labels usually use fewer.