Skip to main content

Molarity Dilution Calculator

Solve one unknown in C1V1 = C2V2 when concentrations are molarities (mol/L) or any matching concentration unit. Leave exactly one of C1, V1, C2, V2 blank. Not a lab protocol.

Rated 4.8 out of 5 based on 221 reviews

Results

How to dilute by molarity

  1. Enter stock molarity C1 and the stock volume V1 you will pipette or measure.
  2. Enter the target molarity C2. Leave V2 blank to solve how much final solution that produces.
  3. Or leave any other single field blank when three values are known.
  4. Keep concentration units matched on C1 and C2, and volume units matched on V1 and V2.

Molar dilution

C1V1 = C2V2 for concentration and volume

C1Stock concentration (often mol/L)
V1Stock volume transferred
C2Final diluted concentration
V2Final diluted volume
ConservationMoles of solute stay constant: C1V1 = C2V2
Solvent addedV2 − V1 when volumes share a unit

What molar dilution conserves

Dilution keeps solute moles constant while volume rises and concentration falls. From 10 mol/L stock, 1 volume unit diluted to 1 mol/L needs 10 volume units of final solution.

Stock, aliquot, and final solution

Stock is the concentrated reagent. The aliquot is V1 taken from that stock. Final solution is the mixture after adding solvent to reach V2 at C2.

How C1V1 = C2V2 is solved

Leave exactly one variable blank. The page rearranges the product equality for that blank. Known concentrations and volumes must be greater than zero.

Limits

Assumes ideal mixing and conserved solute. Not a protocol, SDS, or pipette training guide. See the disclaimer.

Molarity dilution questions

How is this different from the general dilution page?
Same C1V1 = C2V2 engine. This spoke focuses on molar stock and target concentrations with lab-style labels.
Do C1 and C2 have to be mol/L?
They must share a unit. Mol/L is common, but any matching concentration unit works in the arithmetic.
How much solvent do I add?
If V1 and V2 use the same unit, solvent added is V2 minus V1 after you solve V2.
Why leave V2 blank in the default?
So the page demonstrates solving final volume from stock molarity, stock volume, and target molarity.
Can I solve for stock molarity?
Yes. Enter V1, C2, and V2. Leave C1 blank.