Dilution calculator FAQ for formulas, SI units, molarity, and solution preparation

Match the calculator to the unknown quantity. Use dilution for a stock aliquot, serial dilution for repeated transfers, molarity for mass-concentration-volume relationships, reconstitution for volume from mass concentration, percent solution for w/v, v/v, or w/w, and the molecular converters when changing mg/mL to molarity or moles to mass.

Enter stock concentration C1, desired final concentration C2, and total final solution volume V2. The calculator solves stock volume V1 using C1V1 = C2V2, then reports the mathematical diluent volume and dilution factor. V2 is the finished solution volume, not the amount of solvent added before mixing.

Yes. Concentration fields independently support fM, pM, nM, µM, mM, and M. Values are converted to mol/L before the dilution equation is evaluated. Always confirm that C1 and C2 describe the same concentration basis; molarity and a mass concentration such as mg/mL are not directly interchangeable.

Choose µL beside the V1 result and calculate again. One mL equals 1,000 µL, so 0.1 mL is 100 µL. The physical volume does not change when the display unit changes. Check that the converted result remains inside the reliable range of the selected pipette or dispenser.

For a direct dilution, dilution factor equals normalized stock concentration C1 divided by final concentration C2. It is also equal to total final volume V2 divided by transferred stock volume V1. A 200-fold dilution means the final concentration is one two-hundredth of the starting concentration.

Dilution lowers the concentration of an existing solution by transferring a portion into a larger final volume. Reconstitution creates a solution from a measured mass and a target mass concentration. The equations, input units, and interpretation of solvent or final volume are different, so the pages should not be used interchangeably.

Molarity is amount of substance per solution volume and uses M, mM, µM, or nM. Mass concentration is mass per solution volume and uses units such as mg/mL or g/L. Molecular weight connects grams and moles, so it is required when converting between these two concentration types.

Yes. Select Mass, Concentration, or Volume as the unknown. The calculator rearranges mass = concentration × volume × molecular weight and normalizes mass to grams, concentration to mol/L, and volume to liters before returning the answer in the selected display unit.

Use the molecular weight, molar mass, or formula weight for the exact material represented by the mass measurement. Salt form, hydration, counterions, isotopic labels, and conjugation can change the correct value. Prefer the batch label or certificate of analysis instead of a generic value remembered from another product form.

A single-step dilution transfers one stock aliquot directly into a final solution. A serial dilution repeats a defined factor from one tube to the next and produces a concentration sequence. Serial preparation is useful when a direct transfer would be too small to measure reliably or when multiple assay concentrations are needed.

Yes. Enter the starting concentration, target concentration, number of equal steps, and final volume per tube. The calculator solves the common per-step factor and generates a preparation table. Mix each tube before the next transfer and account for any volume that must remain after downstream sampling.

Weight/volume uses solute mass per final solution volume, volume/volume uses solute volume per final solution volume, and weight/weight uses solute mass per total solution mass. Do not change only the label: conversions between these definitions require density and sometimes temperature or composition data.

Not always. Final volume is the completed solution volume after the solute and solvent are combined. Dissolving a solid or mixing liquids can change volume, so a procedure may instruct you to dissolve in less solvent and then bring the mixture to a final mark instead of adding the arithmetic remainder directly.

Normalize the mass concentration to grams per liter and divide by molecular weight in grams per mole. One mg/mL equals one g/L. The result is mol/L and can then be converted to mM, µM, or nM. The reverse calculation multiplies molarity by molecular weight before converting mass concentration units.

Use it when the question contains amount of substance and molecular weight but no concentration or solution volume. Multiply moles by grams per mole to find mass, or divide mass by molecular weight to find moles. Use the molarity calculator when concentration and final volume are also part of the relationship.

Do not assume extra decimal places make a transfer measurable. Compare the result with the validated range and uncertainty of the available pipette. An intermediate or serial dilution can replace one very small direct transfer with several larger transfers, but every added step introduces its own mixing and measurement uncertainty.

The current calculators run in the browser and do not send the entered concentration, mass, volume, percent, molecular weight, or amount values to an application endpoint. The site does not create an account-based calculation history. Standard hosting request logs remain separate from values typed into calculator fields.

No. Purity corrections, density, displacement, activity, solubility, stability, non-additive volumes, and equipment uncertainty require product- or method-specific information outside these equations. Apply a correction only when the governing procedure defines it, and document the source and basis used.

Round the final value to a precision supported by the least precise input and the laboratory equipment. Extra digits displayed by software do not create measurement precision. Keep the unrounded value only for intermediate arithmetic when required, then report a result consistent with balance, pipette, or flask tolerance.