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Normality to Molarity Converter
↔ Convert M to N instead

Common Conversions

N M
0.01 0.01
0.05 0.05
0.1 0.1
0.25 0.25
0.5 0.5
1 1
2 2
5 5

Why this conversion matters in chemistry

Older titrant bottles still often read in normality — 0.1 N HCl, 0.1 N H₂SO₄, 0.1 N NaOH — even though the reaction math downstream usually wants molarity. Converting is one division: M = N ÷ n, where n is the number of equivalents per formula unit in the specific reaction you're running. 0.1 N HCl is 0.1 M because HCl donates one proton; 0.1 N H₂SO₄ is 0.05 M because it donates two. Permanganate running as a 5-electron oxidant at 0.1 N is 0.02 M. The trap is remembering that n belongs to the reaction, not the compound — if you're using phosphoric acid and only titrating to the first endpoint, n is 1, not 3.

Formula

M = N ÷ n (where n depends on the substance and reaction)

Worked Examples

1 N HCl = 1 M

One proton per molecule means N and M match. The easy case.

1 N H₂SO₄ = 0.5 M

Two dissociable protons, so molarity is half the normality. A 1 N H₂SO₄ bottle contains half as many moles as a 1 N HCl bottle.

1 N NaOH = 1 M

One hydroxide per formula unit — normality and molarity coincide, same as HCl but on the base side.

0.1 N KMnO₄ = 0.02 M

Redox rather than acid-base. Permanganate picks up 5 electrons in acidic conditions, so n = 5 and the molarity is a fifth of the normality.

Frequently Asked Questions

How do I convert normality to molarity?
Divide by the equivalence factor n for your specific reaction. For sulfuric acid under standard acid-base conditions, M = N ÷ 2. For phosphoric acid fully deprotonated, M = N ÷ 3. The number is reaction-specific, not a compound property. The table below shows the n = 1 case (M = N, matching HCl or NaOH); for higher-n reagents, divide the normality column by your reaction's actual n.
What's n for the common acids and bases?
HCl, HNO₃, NaOH, KOH all have n = 1 — one dissociable proton or hydroxide. H₂SO₄ and Ca(OH)₂ are n = 2. H₃PO₄ and Al(OH)₃ are n = 3, though phosphoric acid is often titrated only partway and used at n = 2 in practice.
Can the same solution have different normalities?
Yes — and that's the main reason chemistry drifted away from normality. Phosphoric acid can be 1 N, 2 N, or 3 N depending on which endpoint you titrate to. The number depends on the experiment, not just the bottle, so you have to keep the reaction context in your head every time.
Why do some labs still use normality?
It cleans up titration math. At the endpoint, N₁V₁ = N₂V₂, regardless of how many protons or electrons the species exchange — no need to carry stoichiometric coefficients through the calculation. That convenience kept it alive in volumetric titrations, water treatment, and clinical chemistry even after molarity became dominant elsewhere.