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Molarity to g/L Converter
↔ Convert g/L to M instead

Common Conversions

M g/L
0.001 0.058
0.01 0.584
0.05 2.922
0.1 5.844
0.25 14.61
0.5 29.22
1 58.44
2 116.88
5 292.2
10 584.4
12 701.3

Why this conversion matters in chemistry

A protocol calls for 137 mM NaCl in a phosphate-buffered saline; a balance can only weigh in grams. Multiplying molarity by molar mass closes that gap. NaCl at 0.137 M and 58.44 g/mol comes out to 8.01 g per liter — the value that goes onto the prep sheet for a Western-blot transfer buffer or a cell-culture wash. The conversion is the standard step every wet-lab buffer preparation runs through, and the reason a chemistry stockroom keeps molar masses written next to the bottles.

Formula

g/L = M × MW (molar mass in g/mol)

Worked Examples

1 M NaCl = 58.44 g/L

One molar sodium chloride — the canonical reference, since NaCl's molar mass is the textbook example.

0.1 M NaOH = 4 g/L

A dilute sodium hydroxide working solution — useful for a quick titration or a pH adjustment.

0.5 M glucose = 90.08 g/L

Half-molar glucose — about 9% w/v, a common concentration in cell-culture media.

6 M HCl = 218.76 g/L

Concentrated hydrochloric acid for stripping, dissolution, or aggressive cleaning — the working dilution from a 12 M stock.

Frequently Asked Questions

How do I convert molarity to g/L?
Multiply by the molar mass in g/mol. So 1 M NaCl is 1 × 58.44 = 58.44 g/L. The relationship is exact for any solute whose molar mass is known cleanly.
Why do I need the molar mass?
Molarity counts molecules per liter; g/L weighs them out. Molar mass is the bridge that converts between amount and mass — without it, the same molarity gives wildly different g/L values for different compounds.
Can I do the conversion without knowing the solute?
No. NaCl (58.44 g/mol), NaOH (40), and glucose (180.16) all produce different g/L for the same molarity. The compound identity sets the conversion factor.
How do I prepare a 1 M NaCl solution?
Dissolve 58.44 g of NaCl in distilled water to a final volume of 1 L. Use a volumetric flask for accuracy — the dissolved-volume difference matters at higher concentrations.