Concentration Converter (Density-Aware)

Convert M (mol/L), m (mol/kg), wt%, vol%, and ppm together

Shows missing inputs only when a conversion needs them ppm/vol% basis is fixed and displayed in the results Paste a table to batch-convert multiple rows

LIVE Results update as you type

Inputs (Minimal Set)

Input format Halaga

ppm basis vol% basis

Significant figures Notation

Additional Inputs (Only When Needed)

Molar mass (g/mol) — required for M/m conversions Example: NaCl = 58.44

Solution density ρ (g/mL) — required for wt% ↔ M / ppm(w/w) ↔ M Solute density (g/mL) — required for vol% (v/v)

Density unit Temperature (optional)

Density depends on temperature. The entered temperature is shown in the assumptions chips.

Mga Resulta

Unit	Halaga	Action
M (mol/L)	—
m (mol/kg solvent)	—
wt% (w/w)	—
vol%	—
ppm	—

Batch Conversion (Paste Table)

Paste from Excel/Sheets (TSV/CSV supported). Missing columns fall back to common settings.

COMMON Common settings apply when a column is blank

Molar mass (g/mol) Solution density ρ (g/mL) Solute density (g/mL) Density unit ppm basis vol% basis

Table data

Show formulas & assumptions

Mga Kahulugan

M: mol/L (solution volume basis)
m: mol/kg solvent (solvent mass basis)
wt%: w/w = mass fraction × 100
vol%: v/v = volume fraction × 100
ppm: basis selectable

Key equations

M → wt%: wt% = 100 * (M * MW) / (ρ * 1000)
wt% → M: M = (w * ρ * 1000) / MW
M ↔ m: m = 1000*M / (1000*ρ - M*MW)
wt% → m: m = (1000*w) / (MW*(1 - w))
ppm(w/w) ↔ wt%: ppm = 1e6 * w, wt% = ppm / 10000
ppm(w/v) → M: M = (ppm/1000) / MW
vol%(v/v) → M: M = (ρ_solute * v * 1000) / MW

Mga Tala

vol% (v/v) is based on final solution volume.
Solute volume is derived from pure-solute density; volume contraction is ignored.
Errors increase for high concentration, strong electrolytes, or multi-solute systems.

Use Cases

mol/L (M) and wt% conversion

M↔wt% requires solution density and molar mass. If density is unknown, you can still convert wt%↔ppm(w/w) without it.

ppm conversion (choose w/w or w/v basis)

Pick the ppm basis: w/w (mg/kg), w/v (mg/L), or v/v (µL/L). The selected basis is always shown with the results.

molality (m) converter: mol/kg to M

m↔M requires solution density and molar mass. m↔wt% can be calculated with molar mass only.

Monthly rent increase

I don't know the density.

Conversions that don't require density (e.g., wt% ↔ ppm(w/w)) are still shown. When density is required (e.g., M ↔ wt%), the result shows the missing input explicitly.

Which ppm basis is used?

ppm can be w/w (mg/kg), w/v (mg/L), or v/v (µL/L). You select the basis and the result displays it clearly.

Can I calculate multiple rows at once?

Yes. Paste a table of rows. Common settings can fill missing columns for batch conversion.

Important notes

ppm has multiple definitions. Always confirm the basis (w/w, w/v, v/v).
Density is temperature-dependent. Enter the density at the target temperature for accuracy.
Converting vol% (v/v) uses solute density and ignores volume contraction, which can introduce error.
This tool assumes a single solute; multi-component systems require a different approach.