What this converter does
This tool converts solution concentrations between three common units: percent weight/volume (% w/v), milligrams per millilitre (mg/mL), and parts per million (ppm). It uses the standard relationship for dilute aqueous solutions: 1% w/v = 10 mg/mL = 10,000 ppm. Enter any value, pick its unit, and you instantly get all three equivalents.
How to use it
Type your concentration value, choose whether it is in % w/v, mg/mL, or ppm, and submit. The calculator first converts your input to a common base (mg/mL), then expresses it in every unit. % w/v means grams of solute per 100 mL of solution, so 1 g per 100 mL equals 10 mg/mL.
The formula explained
Because 1 g = 1000 mg and 100 mL is the % w/v reference volume, 1% w/v = 1000 mg / 100 mL = 10 mg/mL. For dilute water-based solutions where 1 mL ≈ 1 g, 1 mg/mL ≈ 1000 ppm. Chaining these gives 1% w/v = 10 mg/mL = 10,000 ppm.
$$\text{mg/mL} = \text{Value (\% w/v)} \times 10, \quad \text{ppm} = \text{mg/mL} \times 1000$$
Worked example
You have a 0.9% w/v saline solution. Multiply by 10: \(0.9 \times 10 = 9\) mg/mL. Multiply by 1000: \(9 \times 1000 = 9{,}000\) ppm. So normal saline is 9 mg/mL or 9,000 ppm of sodium chloride.
FAQ
Is ppm exactly mg/L? For dilute aqueous solutions with density near 1 g/mL, 1 ppm ≈ 1 mg/L, and 1 mg/mL = 1000 mg/L = 1000 ppm. The approximation holds well for dilute solutions.
What is % w/v? Percent weight per volume: grams of solute dissolved per 100 mL of solution.
Does density matter? The ppm conversion assumes solution density of about 1 g/mL (typical for water). For very concentrated or non-aqueous solutions, correct for actual density.
