FormatFlow

No tool matches “”

Try a format (“webp”, “mp3”) or a verb (“merge”, “compress”).

PDF toolsImage toolsVideo toolsAll tools

Loading index

↵to open

Chemistry Tools · Updated October 21, 2026 · Reviewed by FormatFlow Editorial

Solution Preparation Calculator

You can calculate the mass of solid needed to make a solution of a target concentration and volume, or the stock and diluent volumes needed to dilute a stock solution.

Runs in your browserFree · No sign-up · No watermark
CONCENTRATION → MASSRuns in your browser
Loading the tool…

Everything runs locally in this tab. No file is uploaded while the tool loads.

This tool runs in your tab. Nothing is uploaded and no copy is stored.

How files are handled

At a glance

Works with
CONCENTRATION → MASS
Processing
In your browser
Price
Free, no account
Updated
October 21, 2026
All Chemistry Tools

About Solution Preparation Calculator

Preparing a solution of known concentration means weighing the right amount of solid or diluting a stronger stock by the right factor. The arithmetic is simple, but mixing units or missing the final volume is a common source of lab errors.

This calculator has two routes. From solid it returns the mass needed for a target molarity and volume using the solute's formula molar mass; from stock it returns the stock volume V1 = C2V2/C1 and the diluent volume, with the dilution factor and every conversion shown.

What this tool does

The details that matter when you use Solution Preparation Calculator for real work.

  • Two preparation routes

    Calculate the mass of solute for a solution made from solid, or the stock volume for a dilution from a more concentrated solution.

  • Formula molar mass

    The solute formula is parsed with the shared formula parser, so NaCl, CuSO4 or a hydrate gives its molar mass without a separate lookup.

  • Mixed units

    Concentration can be entered in M or mM and volume in L or mL; the arithmetic converts to mol/L and liters internally.

  • Dilution guard rails

    The target concentration must be below the stock concentration for a dilution; equal concentrations are flagged as a no-op instead of producing misleading volumes.

  • Dilution factor

    The summary states the factor C1/C2 and the diluent volume, which is what a lab protocol usually asks for.

  • Steps and caveats

    Both routes show the substituted formulas, unit conversions and a reminder that purity, assay and lab safety procedures are outside the arithmetic.

How to use Solution Preparation Calculator

No account, no installation — the whole job happens in this browser tab.
  1. 01

    Choose the route

    Pick from solid to weigh a solute, or from stock to dilute an existing solution.

  2. 02

    Enter the target solution

    For a solid, enter the target concentration and final volume; for a dilution, also enter the stronger stock concentration.

  3. 03

    Add the formula

    Type the solute formula when preparing from solid so the calculator can use its molar mass to find the required mass.

  4. 04

    Read the result

    From solid, the result is the mass to weigh; from stock, it is the stock volume V1, the diluent volume and the dilution factor.

  5. 05

    Check the steps

    Review the concentration and volume conversions and the substituted formulas, then follow your lab protocol for the actual preparation.

How this tool works

Works with
CONCENTRATION → MASS
Processing
Client-side, in your browser. Nothing is uploaded.
Requirements
Chrome, Edge, Firefox or Safari · JavaScript enabled

Limitations worth knowing

  • Assumes ideal solution volumes add, so it does not correct for volume contraction, temperature changes or mixing effects.
  • Does not account for solute purity or assay, and does not adjust for hydrates beyond the formula's own water content.
  • An arithmetic aid only: it does not replace a lab protocol or the safety procedures for the specific chemicals involved.

Privacy and file handling

Concentrations, volumes and solute formulas are processed in your browser tab. Nothing is uploaded, stored or logged, and the calculator makes no network request.

Read the full privacy policy

Solution Preparation Calculator FAQ

Short, direct answers to the questions people ask before using this tool.
How do I calculate the mass needed to prepare a solution?
Multiply the target concentration in mol/L by the final volume in liters and by the solute's molar mass: m = C × V × M. For 250 mL of 0.100 M NaCl, that is 0.100 × 0.250 × 58.44 = 1.461 g of NaCl.
How do I dilute a stock solution?
Use C1V1 = C2V2: the stock volume is V1 = C2V2/C1, and the diluent volume is V2 − V1. To turn 250 mL of 0.100 M from a 1.00 M stock, V1 = 0.100 × 250 / 1.00 = 25.0 mL of stock plus 225 mL of diluent.
Why must the target concentration be lower than the stock concentration?
Dilution only lowers concentration, so C2 must be below C1. To increase concentration you would need to evaporate solvent, add more solute or use a more concentrated stock; entering C2 above C1 is rejected rather than producing a negative diluent volume.
Do I add the stock to the solvent or the solvent to the stock?
It depends on the chemistry and the lab protocol; for concentrated acids the usual rule is to add acid to water, never water to concentrated acid. A common volumetric technique is to add the stock to the flask, then bring the total to the mark with diluent, and mix thoroughly.
Does the calculator account for purity or assay?
No. The mass is calculated for 100% pure solute. If the solid has a stated assay such as 98%, divide the required mass by 0.98 before weighing, and if the solute is a hydrate remember that the formula mass already includes the water.
Can I mix mM and mL in the same calculation?
Yes. The concentration unit switch accepts M or mM and the volume unit switch accepts L or mL, and both are converted internally to mol/L and liters before the multiplication, so mixed units are safe.
What is the dilution factor?
The dilution factor is how many times the solution was diluted, equal to C1/C2 and also to V2/V1. A 1.00 M stock taken to 0.100 M has a factor of 10, which means one part stock to nine parts diluent by volume.

Background reading

Format guides that explain the trade-offs behind Solution Preparation Calculator.