PPM、%VOL、PPB Converter

Parts per Million.  Imagine that:  one target gas molecule among a million air molecules,  that's 1 PPM.

Parts per Billion.  Imagine that:  one target gas molecule among a billion air molecules,  that's 1 PPB.

Out of one hundred air molecules, how many are the target gas molecules.

PPM (parts per million) is a unit used to measure very low concentrations of substances in larger mixtures. It is commonly used to measure gas concentrations in air (pollutants like CO, SO₂, NOx, toxic gases like H₂S, NH₃, combustible gases like CH₄, C₃H₈, and indoor air quality parameters). In liquids, especially water, it measures dissolved oxygen, chlorine, heavy metals, contaminants, and hardness. For solids, PPM is used for trace elements in metals, contaminants in food, and dopants in semiconductors.

1 PPM (parts per million) is equivalent to 1 part of a substance per 1 million parts of the total mixture. For example, in the context of gas concentrations, it means 1 molecule of the target gas per 1 million molecules of air.

PPM stands for "parts per million." It is a unit of measurement used to express very low concentrations of substances, particularly when the amount of the substance is very small compared to the total mixture. It is commonly used for gases, liquids, and even solid materials.

To calculate PPM concentration, you can use the formula:

PPM=( total mass of the mixture / mass of the substance ) × 1,000,000

For gases, it can also be expressed as a volume ratio:

PPM=( total mass of the mixture / mass of the substance ) × 1,000,000

1000 ppm = 0.1%

10000 ppm = 1%

50 ppb = 0.05 ppm

No, they are not the same, especially for gases. PPM is a ratio of volumes (or sometimes masses), while mg/L is a mass-to-volume ratio. PPM is dimensionless, whereas mg/L has units of mass per unit volume.