Solution Dilution Calculator
Diluting a stock solution follows one rule: C₁V₁ = C₂V₂, where C₁ and V₁ are the concentration and volume of the concentrated stock and C₂ and V₂ are the concentration and volume after dilution. Because moles of solute are conserved, the product of concentration and volume stays the same. Pick which of the four quantities you want to solve for, enter the other three, and this calculator returns it — most often the volume of stock to pipette to reach a target concentration and volume. It also tells you how much solvent (water/buffer) to add, which is simply the final volume minus the stock volume. Concentration accepts µM/mM/M or %, volume accepts µL/mL/L; both sides use the same unit so the ratio is consistent.
Stock volume (V₁)
10 mL
Solvent to add: 90 mL
C₁ × V₁ = C₂ × V₂
C₁V₁ = C₂V₂. Solvent to add = final volume − stock volume. Both concentrations (and both volumes) must share a unit.
How to use
- Choose which quantity to solve for: C₁, V₁, C₂ or V₂.
- Pick the concentration and volume units, then enter the three known values.
- Read the result and the volume of solvent to add to reach the final volume.
Frequently asked questions
- What is the dilution formula?
- C₁V₁ = C₂V₂. The concentration times volume of the stock equals that of the diluted solution, because the amount of solute does not change.
- How much stock do I need for a dilution?
- Solve for V₁ = C₂V₂ / C₁. To make 100 mL of 1 M from a 10 M stock, take 1 × 100 / 10 = 10 mL of stock and add 90 mL of solvent.
- What is a dilution factor?
- The ratio C₁/C₂ (equivalently V₂/V₁). A 10 M stock diluted to 1 M is a 10× (1:10) dilution.
- Do the units have to match?
- Both concentrations must use the same unit and both volumes the same unit, since C₁V₁ = C₂V₂ is a ratio. This tool enforces that with shared unit pickers.
Related tools
Molarity Calculator
Convert between mass, moles, volume and molar concentration of a solution — solve for molarity, the mass to weigh out, or the volume to make up.
Two's Complement Converter (8–64 bit)
Enter a decimal, hex, binary, or octal value and see its 8/16/32/64-bit two's complement bit pattern, plus its signed and unsigned readings, hex, octal, and one's complement — in your browser.
Aspect Ratio Calculator
Convert between width × height and aspect ratio (16:9, 4:3, 21:9, …) — fit any ratio inside a container.
Resistor Color Code Calculator
Decode 4/5/6-band axial resistors into ohm value with tolerance — interactive color picker, gold/silver multipliers and tolerances supported.
Capacitor Code Calculator
Decode 3-digit ceramic capacitor codes (104, 473K, 4R7) into picofarads, nanofarads and microfarads, with the tolerance-letter lookup.
Ohm's Law Calculator
Solve V, I, R, P from any two known values. V=IR, P=VI, P=V²/R, P=I²R — pick which pair you have, get the other two instantly.