Chemistry Calculators — Moles, Molarity, pH & More

Free chemistry calculators covering mole conversions (grams, atoms, liters), molarity and molality, pH calculations, parts-per-million (PPM) converters, percent yield, theoretical yield, half-life decay, and stoichiometry — all with step-by-step formulas and reference tables.

All Chemistry Calculators

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Atoms to Moles Calculator

Convert atoms or molecules to moles using Avogadro's number (6.022 × 10²³). Enter the number of particles to find moles.

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Grams to Moles Calculator

Convert grams to moles using molar mass. Enter mass and molar mass to calculate moles, atoms, and molecules.

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Half-Life Calculator

Calculate radioactive decay using the half-life formula N = N₀ × (½)^(t/t½). Find remaining quantity and percent decayed.

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Liters to Moles Calculator

Convert liters of gas to moles at STP (22.414 L/mol) or custom temperature and pressure using the ideal gas law PV = nRT.

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mg/L to PPM Converter

Convert milligrams per liter (mg/L) to parts per million (ppm). For water: 1 mg/L ≈ 1 ppm.

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Molality Calculator

Calculate molality (mol solute / kg solvent). Temperature-independent concentration unit for colligative properties.

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Molar Mass Calculator

Calculate molar mass (g/mol) from mass and moles. Reference table of common elements and compounds included.

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Molarity Calculator

Calculate molarity (M = mol/L) — the most common concentration unit in chemistry. Includes dilution formula M₁V₁ = M₂V₂.

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Mole Calculator

Universal mole converter — convert between grams, atoms/molecules, and liters (at STP). The central concept of chemistry.

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Mole Fraction Calculator

Calculate mole fraction (χ) for a mixture. Mole fractions are dimensionless and always sum to 1.

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Percent to PPM Converter

Convert percentage (%) to parts per million (ppm). 1% = 10,000 ppm.

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Percent Yield Calculator

Calculate percent yield from actual and theoretical yield. Evaluate reaction efficiency in lab experiments.

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pH Calculator

Calculate pH from [H⁺] concentration or vice versa. See pOH, [OH⁻], and a reference table of common substances.

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PPB to PPM Converter

Convert parts per billion (ppb) to parts per million (ppm). 1,000 ppb = 1 ppm.

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PPM Calculator

Calculate parts per million (ppm) from a part-to-whole ratio. Used in water quality, air quality, and manufacturing.

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PPM Converter

Universal PPM converter — convert between ppm, percent (%), ppb, and mg/L in one tool with quick reference table.

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PPM to mg/L Converter

Convert parts per million (ppm) to milligrams per liter (mg/L). For water: 1 ppm = 1 mg/L.

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PPM to Percent Converter

Convert parts per million (ppm) to percentage. 10,000 ppm = 1%.

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PPM to PPB Converter

Convert parts per million (ppm) to parts per billion (ppb). 1 ppm = 1,000 ppb.

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Theoretical Yield Calculator

Calculate theoretical yield from reactant mass, molar masses, and stoichiometric ratio. Find the maximum possible product mass.

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💡 Understanding Chemistry Calculations

Chemistry calculations form the bridge between the macroscopic world we observe and the atomic-scale world of molecules and reactions. The mole — Avogadro's number (6.022 × 10²³) — is the central concept, connecting grams to atoms.

These calculators cover the most commonly used chemistry formulas: mole conversions (n = m/M), molarity (M = n/V), pH (pH = -log[H⁺]), stoichiometry, concentration (PPM, PPB), and reaction yield. All use IUPAC-standard definitions and NIST reference values.

Start with the Mole Calculator for basic conversions, pH Calculator for acid-base chemistry, or PPM Calculator for environmental/water quality work.