How It Works
This calculator works in 4 steps.
Choose the ppm basis
Select mg/L (w/v), mg/kg (w/w), or µL/L (v/v).
Enter the stock ppm
Type the concentration of the standard or concentrate.
Enter the target ppm and final volume
Type the working ppm and the volume or mass to prepare.
Read the stock amount
The calculator returns the stock volume or mass and the diluent amount.
The Formula
The formula applies C₁V₁ = C₂V₂ with ppm on one fixed basis.
ppm₁ × V₁ = ppm₂ × V₂1 ppm = 1 mg/L = 1 µg/mL1 ppm = 1,000 ppb = 10⁶ ppt- ppm₁ / ppm₂:
- Stock and target ppm on one basis
- V₁ / V₂:
- Stock and final volumes or masses
To make 1 L of 1 ppm iron standard from a 1,000 ppm stock, V₁ = 1 × 1,000 / 1,000 = 1 mL. Fill to 1,000 mL.
Conversion Table
The conversion table gives stock and diluent volumes for 6 ppm dilutions on the mg/L basis.
| Stock | Target | Final volume | Stock volume | Diluent |
|---|---|---|---|---|
| 1,000 ppm | 10 ppm (10 mg/L) | 100 mL | 1 mL | 99 mL |
| 1,000 ppm | 1 ppm (1 mg/L) | 1,000 mL | 1 mL | 999 mL |
| 100 ppm | 5 ppm (5 mg/L) | 500 mL | 25 mL | 475 mL |
| 10,000 ppm | 200 ppm (200 mg/L) | 1,000 mL | 20 mL | 980 mL |
| 500 ppm | 2 ppm (2 mg/L) | 250 mL | 1 mL | 249 mL |
| 50 ppm | 0.5 ppm (0.5 mg/L) | 100 mL | 1 mL | 99 mL |
What Is the PPM Dilution Calculator?
The PPM Dilution Calculator is a tool that dilutes solutions expressed in parts per million (ppm) on a stated mass-per-volume, mass-per-mass, or volume-per-volume basis. In dilute water solutions, 1 ppm equals 1 mg/L, which equals 1 µg/mL.
ppm is a ratio, not a unit with a fixed basis. 1 ppm by mass in water is 1 mg/kg, 1 ppm by volume in air is 1 µL/L, and 1 ppm by mass-per-volume is 1 mg/L. The calculator asks for the basis and keeps both sides of the dilution on that basis.
Common Uses
There are 5 main uses of this calculator.
AAS and ICP standards
Analysts dilute 1,000 ppm element standards to 0.1 to 10 ppm.
Water treatment
Operators prepare chlorine and fluoride solutions at set ppm.
Sanitizer levels
Food plants dilute sanitizers to 50 to 200 ppm.
Fertigation
Growers dilute nutrient stocks to ppm targets for irrigation.
Gas calibration
Technicians prepare ppm-by-volume gas mixtures for detectors.