How many PPB is 1 g/L?

1 g/L equals 1,000,000 PPB in dilute aqueous solutions at standard conditions. This is because 1 g/L = 1,000 mg/L = 1,000,000 µg/L, and 1 µg/L = 1 PPB for water.

What is the formula to convert g/L to PPB?

PPB = g/L × 1,000,000 ÷ density (g/mL). For water with density 1 g/mL, PPB = g/L × 1,000,000.

Why is PPB used instead of g/L for trace measurements?

PPB (parts per billion) is preferred for very small concentrations because it gives more readable numbers. For example, 0.000015 g/L is easier to read as 15 PPB, which is the US EPA action level for lead in drinking water.

When does the 1 g/L = 1,000,000 PPB rule not apply?

When the solution density deviates significantly from 1 g/mL — for example, concentrated acid solutions, seawater (~1.025 g/mL), or gas-phase measurements. Use the density field in this tool to handle those cases.

How do I convert PPB back to g/L?

g/L = PPB × density (g/mL) ÷ 1,000,000. For water: g/L = PPB ÷ 1,000,000.

What is the relationship between g/L, mg/L, and PPB?

1 g/L = 1,000 mg/L = 1,000,000 µg/L = 1,000,000 PPB (in water). These units are all measuring concentration, just at different scales.

g/L to PPB Converter

Name: g/L to PPB Converter
Availability: InStock
Author: Nham Vu

Enter a concentration in g/L and get the equivalent in PPB instantly. For water, 1 g/L = 1,000,000 PPB.

Conversion Input

Concentration (g/L)

Solution density (g/mL) — leave at 1.0 for water

Result

Enter a value and click Convert to see the result.

Quick Reference — g/L to PPB (water, density = 1 g/mL)

g/L	PPB	Context
0.000001	1	Detection threshold for many contaminants
0.000010	10	EPA arsenic limit in drinking water
0.000015	15	EPA lead action level in drinking water
0.001	1,000	1 mg/L — typical water quality threshold
0.5	500,000	EPA TDS limit for drinking water
1.0	1,000,000	1 g/L = 1,000 mg/L = 1,000,000 PPB

Summary