PPM Converter

Convert Parts-Per Expressions

How to Convert Between Parts-Per Expressions

Converting between different parts-per expressions is essential in chemistry, environmental science, and many other fields. This converter helps you easily transform concentrations from one unit to another.

What are the Formulas?

The key to converting between parts-per expressions is to first convert the input to a decimal (pure ratio) form. From there, we can calculate other units:

  • Decimal = 1
  • Percent (%) = Decimal × 100
  • Per Mille (‰) = Decimal × 1,000
  • Parts per Ten Thousand (‱) = Decimal × 10,000
  • Parts per Hundred Thousand (pcm) = Decimal × 100,000
  • Parts per Million (ppm) = Decimal × 1,000,000
  • Parts per Billion (ppb) = Decimal × 1,000,000,000

What are the conversion steps?

  1. Convert the input value to a decimal (pure ratio) form
  2. Multiply the decimal by the appropriate factor for each unit
  3. Round the results to an appropriate number of significant figures

Example Conversion

Let's convert 500 ppm to other units:

Step 1: Convert to decimal

500 ppm = 500 / 1,000,000 = 0.0005 (decimal)

Step 2: Calculate other units

  • Percent = 0.0005 × 100 = 0.05%
  • Per Mille = 0.0005 × 1,000 = 0.5‰
  • Parts per Ten Thousand = 0.0005 × 10,000 = 5‱
  • Parts per Hundred Thousand = 0.0005 × 100,000 = 50 pcm
  • Parts per Million = 0.0005 × 1,000,000 = 500 ppm
  • Parts per Billion = 0.0005 × 1,000,000,000 = 500,000 ppb

Diagram of Concentration

The following diagram illustrates a 500 ppm concentration:

500 ppm Concentration Solute Solvent 1 million parts total 500 parts solute 999,500 parts solvent

This diagram represents a 500 ppm concentration. The green sliver represents 500 parts of solute, while the blue area represents 999,500 parts of solvent, totaling 1 million parts.