PPM Conversion Chart
Quick reference table to convert parts per million (ppm) to other concentration units. All values assume aqueous solutions (density ≈ 1 kg/L) unless noted.
PPM to All Units — Reference Table
| PPM | Percent (%) | PPB | mg/L | mg/kg | µg/L |
|---|---|---|---|---|---|
| 0.001 ppm | 1.0e-7% | 1 | 0.001 | 0.001 | 1 |
| 0.01 ppm | 1.0e-6% | 10 | 0.01 | 0.01 | 10 |
| 0.05 ppm | 5.0e-6% | 50 | 0.05 | 0.05 | 50 |
| 0.1 ppm | 1.0e-5% | 100 | 0.1 | 0.1 | 100 |
| 0.5 ppm | 5.0e-5% | 500 | 0.5 | 0.5 | 500 |
| 1 ppm | 0.0001% | 1,000 | 1 | 1 | 1,000 |
| 2 ppm | 0.0002% | 2,000 | 2 | 2 | 2,000 |
| 5 ppm | 0.0005% | 5,000 | 5 | 5 | 5,000 |
| 10 ppm | 0.001% | 10,000 | 10 | 10 | 10,000 |
| 15 ppm | 0.0015% | 15,000 | 15 | 15 | 15,000 |
| 20 ppm | 0.002% | 20,000 | 20 | 20 | 20,000 |
| 25 ppm | 0.0025% | 25,000 | 25 | 25 | 25,000 |
| 50 ppm | 0.005% | 50,000 | 50 | 50 | 50,000 |
| 100 ppm | 0.01% | 100,000 | 100 | 100 | 100,000 |
| 200 ppm | 0.02% | 200,000 | 200 | 200 | 200,000 |
| 250 ppm | 0.025% | 250,000 | 250 | 250 | 250,000 |
| 300 ppm | 0.03% | 300,000 | 300 | 300 | 300,000 |
| 400 ppm | 0.04% | 400,000 | 400 | 400 | 400,000 |
| 500 ppm | 0.05% | 500,000 | 500 | 500 | 500,000 |
| 1,000 ppm | 0.1% | 1M | 1,000 | 1,000 | 1M |
| 2,000 ppm | 0.2% | 2M | 2,000 | 2,000 | 2M |
| 5,000 ppm | 0.5% | 5M | 5,000 | 5,000 | 5M |
| 10,000 ppm | 1% | 10M | 10,000 | 10,000 | 10M |
| 35,000 ppm | 3.5% | 35M | 35,000 | 35,000 | 35M |
| 50,000 ppm | 5% | 50M | 50,000 | 50,000 | 50M |
| 100,000 ppm | 10% | 100M | 100,000 | 100,000 | 100M |
| 1,000,000 ppm | 100% | 1B | 1,000,000 | 1,000,000 | 1B |
mg/L and µg/L values assume water (density = 1 kg/L). mg/kg values are always equal to ppm.
Custom PPM Converter
Enter any PPM value to see all conversions:
PPM Conversion Formulas
| Conversion | Formula | Example (1 ppm) |
|---|---|---|
| PPM → Percent | % = ppm ÷ 10,000 | 1 ppm = 0.0001% |
| PPM → PPB | ppb = ppm × 1,000 | 1 ppm = 1,000 ppb |
| PPM → mg/L | mg/L = ppm × density | 1 ppm = 1 mg/L (water) |
| PPM → mg/kg | mg/kg = ppm | 1 ppm = 1 mg/kg (always) |
| PPM → µg/L | µg/L = ppm × density × 1,000 | 1 ppm = 1,000 µg/L (water) |
What is PPM?
PPM (parts per million) expresses a ratio: how many parts of a substance exist per one million parts of the total mixture. It is equivalent to 1 milligram per kilogram (mg/kg) or, in water, 1 milligram per liter (mg/L).
PPM is widely used in:
- Water quality: measuring dissolved solids, chlorine, fluoride, and contaminants
- Environmental science: atmospheric CO₂ levels, soil contamination
- Food safety: pesticide residues, heavy metal limits
- Industry: trace impurities in materials, calibration gases
Common PPM Values
| Context | Substance | PPM | Equivalent |
|---|---|---|---|
| Drinking water | EPA TDS limit | 500 ppm | 500 mg/L |
| Drinking water | EPA lead action level | 0.015 ppm | 15 ppb |
| Drinking water | EPA arsenic limit | 0.010 ppm | 10 ppb |
| Drinking water | Chlorine (typical) | 1–4 ppm | 1–4 mg/L |
| Soil | EPA lead (play areas) | 400 ppm | 400 mg/kg |
| Soil | EPA lead (non-play) | 1,200 ppm | 1,200 mg/kg |
| Atmosphere | CO₂ (current) | ~425 ppm | 0.0425% |
| Seawater | Salinity | ~35,000 ppm | 3.5% |
Frequently Asked Questions
What does PPM stand for?
PPM stands for "parts per million." It expresses a ratio of 1 part per 1,000,000 parts and is used to measure concentration in chemistry, water quality, environmental science, and industry. For example, 1 ppm means 1 milligram of a substance per kilogram of mixture.
How do you convert PPM to percent?
Divide the PPM value by 10,000. For example, 5,000 ppm ÷ 10,000 = 0.5%. This works because 1% = 10,000 ppm (one percent is one part per hundred, and one million divided by one hundred is ten thousand).
Is PPM the same as mg/L?
Only for water and dilute aqueous solutions where density ≈ 1 kg/L. In water, 1 ppm = 1 mg/L. For other solutions with different densities, you must multiply ppm by the solution density (in kg/L) to get mg/L.
However, ppm always equals mg/kg regardless of the substance.
What is the difference between PPM and PPB?
PPM is parts per million and PPB is parts per billion. 1 ppm = 1,000 ppb. PPB is used for much smaller concentrations — for example, EPA's lead action level for drinking water is 15 ppb (0.015 ppm).
How many µg/L is 1 PPM?
For water (density ≈ 1 kg/L), 1 ppm = 1,000 µg/L. This is because 1 ppm = 1 mg/L, and 1 mg = 1,000 µg. For other solutions, multiply ppm by the density (kg/L) and then by 1,000.
All unit conversions on CoolConversion use conversion factors defined or documented by internationally recognised standards bodies (such as ISO and NIST), including both SI and non-SI units.
