Calculate PPM from gallons and solute mass, or solve for the required mass or solution volume, with US, imperial, metric, and density-based options.

Required inputs are marked *. The default aqueous basis treats 1 ppm as approximately 1 mg/L in a dilute, water-like solution.
Enter solute mass and total solution volume.
Use mass fraction when the solution is not water-like or when density is known.
Use the final solution density, not the pure solute density.
PPM concentration
Solute mass
Solution volume
Basis
This calculator treats the entered solute mass as active material. Adjust separately for product purity, and verify chemical labels, density, compatibility, and safe handling before mixing.

PPM from Gallons Formula

The following two example problems outline the steps and information needed to calculate the PPM from Gallons.

PPM = W / G * 119826.427

Variables:

  • PPM is the PPM from Gallons (parts per million)
  • W is the total weight (lbs) 
  • G is the total gallons (gal) 

To calculate PPM from gallons, divide the weight by the gallons, then multiply by 119826.427.

US Gallons to PPM Increase per 1 lb or 1 kg of Solute (1 ppm = 1 mg/L)
Gallons (US) PPM per 1 lb PPM per 1 kg
523,965.352,834.4
1011,982.626,417.2
254,793.110,566.9
303,994.28,805.7
402,995.76,604.3
502,396.55,283.4
552,178.74,803.1
751,597.73,522.3
1001,198.32,641.7
150798.81,761.1
200599.11,320.9
250479.31,056.7
275435.6960.6
300399.4880.6
500239.7528.3
750159.8352.2
1,000119.8264.2
2,00059.9132.1
5,00024.052.8
10,00012.026.4
* Rounded to 1 decimal. Uses 1 lb = 453,592 mg and 1 gal = 3.78541 L. PPM ≡ mg/L. Formulas: ppm per lb = 453,592 ÷ (gal × 3.78541); ppm per kg = 1,000,000 ÷ (gal × 3.78541).

How to Calculate PPM from Gallons?

The following steps outline how to calculate the PPM from Gallons.

  1. First, determine the total weight (lbs). 
  2. Next, determine the total gallons (gal). 
  3. Next, gather the formula from above = PPM = W/G * 119826.427.
  4. Finally, calculate the PPM from Gallons.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

total weight (lbs) = 5

total gallons (gal) = 50

PPM = W/G * 119826.427 = ?