Use this chemistry calculator to reproduce a named relationship with explicit quantities and units for study, laboratory planning, or an independent numerical check.

Calcium concentration (mg/L)

Required number input.

Magnesium concentration (mg/L)

Required number input.

Calculate water hardness as calcium carbonate equivalent from calcium and magnesium concentrations. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Hardness as CaCO3 (mg/L as CaCO3)

The resulting hardness as caco3 returned as a number.

• Environmental metrics are method-dependent and cannot be compared reliably without matching sampling, preservation, digestion, calibration, reporting basis, and detection limits. A calculation alone is not regulatory compliance evidence.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check units and significant figures, compare the result with limiting cases, and use measured or source-specific constants where available. Laboratory, safety, and regulatory decisions require validated methods and appropriate uncertainty analysis.

• Acidity Calculator

  Calculate acidity as calcium carbonate equivalent from base titrant volume, normality, and sample volume.

• Alkalinity Calculator

  Calculate alkalinity as calcium carbonate equivalent from acid titrant volume, normality, and sample volume.

• BOD Calculator

  Calculate biochemical oxygen demand from dissolved-oxygen depletion and a dilution factor.