Parts Per Billion Calculator

Convert between parts per billion (ppb) and other ratio units — percent, ppm, and ppt.

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Enter a ratio value and choose a from/to unit to convert between ppb, ppm, percent, and ppt.

Your result

0.001

Converted value

Equivalent in water (mg/L)0.001

AI explanation

Formula

Converted value = amount × (from-unit-to-fraction factor) ÷ (to-unit-to-fraction factor)

Worked example

1 ppb to ppm

Worked example: 1 ppb to ppm
FieldValue
Amount1
From unitppb
To unitppm
Converted value0.001
Equivalent in water (mg/L)0.001

Assumptions

  • The "equivalent in water" figure assumes a dilute aqueous solution (density ≈1000 g/L), where 1 ppb by mass is very close to 0.001 mg/L (1 µg/L) — a standard approximation in water-quality contexts, but not exact for other solvents or concentrated solutions.

Frequently asked questions

What does 1 ppb mean?

1 part per billion means 1 unit of something in a total of 1 billion units — a thousand times smaller than 1 ppm.

Where are ppb values commonly used?

Trace contaminant testing in drinking water, air quality monitoring for hazardous pollutants, and ultra-trace chemical analysis often report results in ppb.

I need parts per million instead — is there a dedicated version?

Yes — see the Parts Per Million Calculator, which uses the same conversion with ppm as the default unit.

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