Osmolarity & TonicityChemistry

Osmolarity, Osmolality & Solution Tonicity Calculator

Calculate solution osmolarity (mOsm/L), osmolality (mOsm/kg), and clinical tonicity classification (hypotonic, isotonic, hypertonic) for intravenous and physiological fluids.

Calculated Result

Solution Osmolarity

308mOsm/L

Calculator Inputs

M
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Solution Osmolarity

308mOsm/L

Estimated Osmolality

314.16 mOsm/kg

Osmotic Pressure at 37°C

7.84 bar

Osmotic Balance Metrics

Osmolarity
308 mOsm/L(50%)
Osmolality
314.16 mOsm/kg(50%)

Standard biochemical and medical chemistry tool for osmotic balance and intravenous fluid administration.

Calculation Methodology

Osmolarity (mOsm/L) = Molarity (mol/L) * van 't Hoff factor (i) * 1000. Human plasma normal osmolarity is 280-295 mOsm/L.

Frequently Asked Questions

Osmolarity counts all dissolved solute particles, whereas tonicity only considers effective impermeable solutes that pull water across cell membranes.

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