In the US, we usually express water hardness in terms of **PPM** *( Parts Per Million)*. In many cases, however, we would like to express water hardness in

**mg/L of CaCO3**

*(calcium carbonate)*or

**mg/L of Ca**

^{2+}*(calcium ions)*. That’s we have prepared 2 key online tools for converting

**PPM to mg/L**, namely:

**PPM to mg/L Calculator**. You just insert PPMs, and the calculator automatically converts PPM to mg/l of CaCO3 as well as mg/l of Ca^{2+}(you get both results).**PPM to mg/L Charts**. In the*1st chart*, you will see 0-1,000 PPMs converted to*mg/L of CaCO3*. In the*2nd chart*, you will see 0-1,000 PPMs converted to*mg/L of Ca*. We have denoted^{2+}**soft**water*(0-60 ppm)*with,*this green color***moderately hard**water*(61-120 ppm)*with this,*light blue color***hard**water*(121-180 ppm)*with, and*this blue color***very hard**water*(181+ ppm)*with.*this dark blue color*

This conversion is pretty simple. Here are both formulas for this PPM to mg/l (milligrams per liter) conversion:

Water Hardness *(mg/L Of CaCO3)* = **1** Ã— PPM

Water Hardness *(mg/L Of Ca ^{2+})* =

**0.40044**Ã— PPM

Basically, 1 PPM is equal to 1 mg/L of CaCO3, and 1 PPM is equal to 0.40044 mg/L Ca^{2+}.

*Quick Example:* Let’s say we want to convert 100 PPM to mg/L of CaCO3 and Ca^{2+}. This is quite simple. From the equations above (or using the calculator below), we can see that:

*100 PPM*is equal to**100 mg/L of CaCO3**.*100 PPM*is equal to**40.04 mg/L of Ca**.^{2+}

For an even easier calculation, here is the calculator (with an example below), followed by both 1st PPM to mg/L CaCO3 conversion chart and 2nd PPM to mg/L Ca^{2+} conversion chart:

Table of Contents

## PPM To mg/L Calculator

Here is how this online PPM to mg/L calculator works:

Let’s say you have 140 PPM water hardness. How much is that in mg/L of CaCO3 and mg/L of Ca^{2+}? Simply slide the PPM slider in the calculator to ‘*140*‘, and you get both of these results:

140 PPM is equal to **140 mg/L of CaCO3**, and 140 PPM is equal to **56.06 mg/L of Ca ^{2+}** ions.

If you need to convert in reverse – mg/L to PPM – you can use our mg/L to PPM calculator here.

You can find both of these results (as well as many others between 0 and 1,000 PPM) in the charts below. Note that 140 PPM, for example, is considered hard water and is colored in ** this blue color for hard water** in these 2 charts:

### PPM To mg/L Of CaCO3 Chart (1st Chart)

PPM (Parts Per Million): |
mg/L Of CaCO3 (Calcium Carbonate): |

0 PPM | 0 mg/L Of CaCO3 |

1 PPM | 1 mg/L Of CaCO3 |

5 PPM | 5 mg/L Of CaCO3 |

10 PPM | 10 mg/L Of CaCO3 |

15 PPM | 15 mg/L Of CaCO3 |

20 PPM | 20 mg/L Of CaCO3 |

25 PPM | 25 mg/L Of CaCO3 |

30 PPM | 30 mg/L Of CaCO3 |

35 PPM | 35 mg/L Of CaCO3 |

40 PPM | 40 mg/L Of CaCO3 |

45 PPM | 45 mg/L Of CaCO3 |

50 PPM | 50 mg/L Of CaCO3 |

60 PPM | 60 mg/L Of CaCO3 |

70 PPM | 70 mg/L Of CaCO3 |

80 PPM | 80 mg/L Of CaCO3 |

90 PPM | 90 mg/L Of CaCO3 |

100 PPM | 100 mg/L Of CaCO3 |

110 PPM | 110 mg/L Of CaCO3 |

120 PPM | 120 mg/L Of CaCO3 |

130 PPM | 130 mg/L Of CaCO3 |

140 PPM | 140 mg/L Of CaCO3 |

150 PPM | 150 mg/L Of CaCO3 |

160 PPM | 160 mg/L Of CaCO3 |

170 PPM | 170 mg/L Of CaCO3 |

180 PPM | 180 mg/L Of CaCO3 |

190 PPM | 190 mg/L Of CaCO3 |

200 PPM | 200 mg/L Of CaCO3 |

250 PPM | 250 mg/L Of CaCO3 |

300 PPM | 300 mg/L Of CaCO3 |

350 PPM | 350 mg/L Of CaCO3 |

400 PPM | 400 mg/L Of CaCO3 |

450 PPM | 450 mg/L Of CaCO3 |

500 PPM | 500 mg/L Of CaCO3 |

550 PPM | 550 mg/L Of CaCO3 |

600 PPM | 600 mg/L Of CaCO3 |

650 PPM | 650 mg/L Of CaCO3 |

700 PPM | 700 mg/L Of CaCO3 |

750 PPM | 750 mg/L Of CaCO3 |

800 PPM | 800 mg/L Of CaCO3 |

850 PPM | 850 mg/L Of CaCO3 |

900 PPM | 900 mg/L Of CaCO3 |

950 PPM | 950 mg/L Of CaCO3 |

1000 PPM | 1000 mg/L Of CaCO3 |

As you can see, converting PPM to mg/L of CaCO3 is dead simple. Since 1 PPM = 1 mg/L CaCO3, you can see that PPMs and mg/L of CaCO3 (milligrams per liter) are practically the same unit. Hence, we see that:

contains anywhere from*Soft*water**0 to 60 mg/L of CaCO3**.contains anywhere from*Moderately hard*water**61 to 120 mg/L of CaCO3**.contains anywhere from*Hard*water**121 to 180 mg/L of CaCO3**.contains*Very hard*water**more than 181 mg/L of CaCO3**.

The PPM conversion to mg/L of Ca^{2} is a bit more interesting. Here is the whole conversion chart:

### PPM To mg/L Of Ca2+ Ions Chart (2nd Chart)

PPM (Parts Per Million): |
mg/L Of Ca^{2+} (Calcium Ions): |

0 PPM | 0 mg/L Of Ca^{2+} |

1 PPM | 0.40Â mg/L Of Ca^{2+} |

5 PPM | 2.00 mg/L Of Ca^{2+} |

10 PPM | 4.00 mg/L Of Ca^{2+} |

15 PPM | 6.01 mg/L Of Ca^{2+} |

20 PPM | 8.01 mg/L Of Ca^{2+} |

25 PPM | 10.01 mg/L Of Ca^{2+} |

30 PPM | 12.01 mg/L Of Ca^{2+} |

35 PPM | 14.02 mg/L Of Ca^{2+} |

40 PPM | 16.02 mg/L Of Ca^{2+} |

45 PPM | 18.02 mg/L Of Ca^{2+} |

50 PPM | 20.02 mg/L Of Ca^{2+} |

60 PPM | 24.03 mg/L Of Ca^{2+} |

70 PPM | 28.03 mg/L Of Ca^{2+} |

80 PPM | 32.04 mg/L Of Ca^{2+} |

90 PPM | 36.04 mg/L Of Ca^{2+} |

100 PPM | 40.04 mg/L Of Ca^{2+} |

110 PPM | 44.05 mg/L Of Ca^{2+} |

120 PPM | 48.05 mg/L Of Ca^{2+} |

130 PPM | 52.06 mg/L Of Ca^{2+} |

140 PPM | 56.06 mg/L Of Ca^{2+} |

150 PPM | 60.07 mg/L Of Ca^{2+} |

160 PPM | 64.07 mg/L Of Ca^{2+} |

170 PPM | 68.07 mg/L Of Ca^{2+} |

180 PPM | 72.08 mg/L Of Ca^{2+} |

190 PPM | 76.08 mg/L Of Ca^{2+} |

200 PPM | 80.09 mg/L Of Ca^{2+} |

250 PPM | 100.11 mg/L Of Ca^{2+} |

300 PPM | 120.13 mg/L Of Ca^{2+} |

350 PPM | 140.15 mg/L Of Ca^{2+} |

400 PPM | 160.18 mg/L Of Ca^{2+} |

450 PPM | 180.20 mg/L Of Ca^{2+} |

500 PPM | 200.22 mg/L Of Ca^{2+} |

550 PPM | 220.25 mg/L Of Ca^{2+} |

600 PPM | 240.27 mg/L Of Ca^{2+} |

650 PPM | 260.29 mg/L Of Ca^{2+} |

700 PPM | 280.32 mg/L Of Ca^{2+} |

750 PPM | 300.34 mg/L Of Ca^{2+} |

800 PPM | 320.36 mg/L Of Ca^{2+} |

850 PPM | 340.39 mg/L Of Ca^{2+} |

900 PPM | 360.41 mg/L Of Ca^{2+} |

950 PPM | 380.43 mg/L Of Ca^{2+} |

1000 PPM | 400.45 mg/L Of Ca^{2+} |

We see that converting PPM to mg/L of calcium ions is a bit more difficult. We have to multiply PPMs by a factor of 0.40044 to get the mg/L of Ca^{2+}. Here is the water hardness categorization in terms of mg/L of calcium ions:

contains anywhere from*Soft*water**0 to 24.03 mg/L of Ca**.^{2+}contains anywhere from*Moderately hard*water**24.04 to 48.05 mg/L of Ca**.^{2+}contains anywhere from*Hard*water**48.06 to 72.08 mg/L of Ca**.^{2+}contains*Very hard*water**more than 72.09 mg/L of Ca**.^{2+}

Hopefully, this gives you all you need to convert water hardness PPM units to mg/L of CaCO3 and calcium ions. If you need a bit of extraÂ insight about this water hardness unit conversion, you can use the comment section below, give us some numbers, and we will help you out.

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