Chemistry & Biology calculators
Stoichiometry, solutions, equilibrium, thermochemistry, gas laws, genetics and lab calculators.
65 free tools
Most used
Arrhenius Equation CalculatorFind activation energy, or predict a rate constant at a new temperatureAverage Atomic Mass CalculatorWeighted average atomic mass from isotope masses and abundancesBeer-Lambert Law CalculatorSolve A = εlc for absorbance, concentration, ε or path lengthConcentration ConverterConvert molarity, mg/mL, % w/v, % w/w, ppm, molality and mole fractionDalton's Law CalculatorPartial pressures, total pressure and mole fractions of gas mixturesElectron Configuration CalculatorFull and noble-gas electron configurations with orbital diagramsEmpirical Formula CalculatorFind the simplest whole-number formula from percent compositionEnthalpy Change CalculatorReaction enthalpy from heats of formation, or by Hess’s lawFreezing Point Depression CalculatorHow far a dissolved solute lowers the freezing point — or its molar massGibbs Free Energy CalculatorΔG = ΔH − TΔS with spontaneity, crossover temperature and KHardy-Weinberg CalculatorAllele and genotype frequencies with an equilibrium chi-square testHenderson-Hasselbalch CalculatorFind buffer pH, or the base-to-acid ratio for a target pHInteractive Periodic TableAll 118 elements with atomic mass, electron configuration and propertiesMolecular Formula CalculatorTurn an empirical formula or percent composition into the true formulaMoles to Atoms CalculatorConvert moles, grams, molecules and atoms with Avogadro’s numberOxidation Number CalculatorAssign oxidation states to every element in a compound or ionPrimer Melting Temperature CalculatorPrimer Tm by nearest-neighbor, salt-adjusted and Wallace formulasProtons, Neutrons & Electrons CalculatorCount subatomic particles for any element, isotope or ionPunnett Square CalculatorMonohybrid, dihybrid and trihybrid crosses with genotype and phenotype ratiosRPM to RCF CalculatorConvert centrifuge speed in RPM to g-force (×g) and backSpecific Gravity CalculatorSpecific gravity from density or weighing, with Brix, Plato and APIStoichiometry CalculatorGrams to grams and moles to moles for any chemical equationTitration CalculatorFind an unknown concentration or the equivalence-point volume
More chemistry & biology tools
Atom Economy CalculatorSee what share of reactant mass ends up in your desired productAvogadro's Law CalculatorSolve V₁/n₁ = V₂/n₂ for any missing volume or amount of gasBoiling Point Elevation CalculatorFind how much a dissolved solute raises a solvent’s boiling pointBond Energy CalculatorEstimate reaction enthalpy from bonds broken and bonds formedBond Polarity CalculatorClassify a bond as nonpolar, polar covalent or ionic in one stepDNA Concentration CalculatorConvert an A260 reading into ng/µL, total yield and purity ratiosDNA Reverse Complement ToolGet the reverse, complement and reverse complement of DNA or RNA instantlyDNA to Protein TranslatorTranscribe DNA to mRNA and translate codons into amino acidsDoubling Time CalculatorFind generation time, growth rate and number of doublings for cellsElectrolysis Calculator (Faraday's Law)Mass deposited, time or current needed in electrolysis and platingEquilibrium Constant CalculatorFind Kc, Kp or the reaction quotient Q for aA + bB ⇌ cC + dDFormal Charge CalculatorFC = valence − nonbonding − ½ bonding, for any atom in a Lewis structureGay-Lussac's Law CalculatorSolve P₁/T₁ = P₂/T₂ for a gas at constant volumeGC Content CalculatorGC percentage, base counts and GC skew of any DNA or RNA sequenceHemocytometer Cell Count CalculatorTurn hemocytometer counts into cells/mL, viability and seeding volumeKa & pKa CalculatorConvert Ka, pKa, Kb and pKb and find the pH of a weak acid or baseLogistic Growth CalculatorModel S-curve population growth that levels off at carrying capacityMolar Volume CalculatorConvert moles of gas to liters (and back) at STP, SATP or any conditionsNernst Equation CalculatorCell potential under non-standard concentrations and temperaturesNormality CalculatorNormality, equivalent weight and grams needed for acid, base and redox solutionsOsmotic Pressure CalculatorΠ = iMRT for any solution, or find a molar mass from measured osmotic pressurePCR Master Mix CalculatorScale buffer, dNTPs, primers, enzyme and water for any number of reactionsRf Value CalculatorFind the retention factor of up to three TLC or paper chromatography spotsSerial Dilution CalculatorPlan a dilution series: transfer volumes and the concentration of every tubeStandard Cell Potential CalculatorPick two half-reactions and get E°cell, ΔG° and K instantlyVSEPR Molecular Geometry CalculatorPredict molecular shape, bond angles and hybridization from electron domainsWater Hardness CalculatorConvert hardness between ppm, gpg, °dH, °fH, °e and mmol/L — or from Ca and MgClausius-Clapeyron CalculatorFind vapor pressure, boiling temperature or enthalpy of vaporizationDegree of Unsaturation CalculatorCount rings plus π bonds (double bond equivalents) from a molecular formulaDNA Copy Number CalculatorConvert a DNA or RNA mass into number of copies, picomoles and copies per µLGraham's Law CalculatorCompare effusion rates of two gases or find an unknown molar massICE Table CalculatorSolve equilibrium concentrations for aA + bB ⇌ cC + dD from K and initial valuesIntegrated Rate Law CalculatorConcentration, time, rate constant and half-life for 0th, 1st and 2nd orderIonic Strength CalculatorIonic strength of any salt or ion mixture, with activity coefficientsLigation CalculatorHow many ng of insert you need for a 3:1 (or any) insert:vector ratioPercent Solution CalculatorHow much solute for a w/v, w/w or v/v percent solution — or what % you haveProtein Molecular Weight CalculatorPeptide and protein mass, extinction coefficient and composition from sequenceRaoult's Law CalculatorVapor pressure of a solution — non-volatile solute or two volatile liquidsRate Law CalculatorFind reaction orders and the rate constant from initial-rate dataRydberg Equation CalculatorWavelength, frequency and energy of hydrogen spectral linesUnit Cell Density CalculatorDensity, edge length, atomic radius and packing efficiency of cubic cellsVan der Waals Equation CalculatorReal-gas pressure, volume or temperature, compared with the ideal gas law