Developer Utilities
Small developer utilities that save a trip to a random website. Encode and decode Base64, explain a regex, build UTM links, generate QR codes and vCards, and more — the everyday helpers. Free in your browser, and available by API when you need them in a script.
Developer Utilities
Ideal gas law chemistry calculator
solve PV = nRT for P, V, n, or T
POST /chem/ideal-gas$0.002Developer Utilities
Integrated rate law order checker
which plot is linear, free
POST /chem/integrated-rate-order$0.002Developer Utilities
Internal energy change calculator
ΔU = Q − W first law, free
POST /chem/internal-energy-change$0.002Developer Utilities
Ionic strength calculator
I = ½ Σ c_i z_i² free
POST /chem/ionic-strength$0.002Developer Utilities
Isotope abundance calculator
percent from average mass, free
POST /chem/isotope-abundance$0.002Developer Utilities
Ka from pH calculator
acid dissociation from concentration and pH, free
POST /chem/ka-from-ph$0.002Developer Utilities
Kb from pKb calculator
base dissociation constant Kb = 10^(−pKb), free
POST /chem/kb-from-pkb$0.002Developer Utilities
Kc from degree of dissociation calculator
equilibrium constant from α and c₀, free
POST /chem/kc-from-dissociation$0.002Developer Utilities
Kp from Kc calculator
convert with T and Δn, free
POST /chem/kp-kc-conversion$0.002Developer Utilities
Lattice energy calculator
Born–Landé equation, free
POST /chem/lattice-energy-born-lande$0.002Developer Utilities
Product mass from limiting reactant calculator
two reagents, free
POST /chem/limiting-reactant-product-mass$0.002Developer Utilities
Mass fraction calculator
w and mass % from solute and total mass, free
POST /chem/mass-fraction$0.002Developer Utilities
Mass fraction to mole fraction calculator
free
POST /chem/mass-fraction-to-mole-fraction$0.002Developer Utilities
Pure mass from purity calculator
impure sample to pure substance mass, free
POST /chem/mass-from-purity$0.002Developer Utilities
Mass of element in sample calculator
m_element from sample mass and mass fraction, free
POST /chem/mass-of-element-in-sample$0.002Developer Utilities
Mass of product from reactant calculator
grams via mole ratio, free
POST /chem/mass-of-product-from-reactant$0.002Developer Utilities
Mass percent calculator
w/w concentration from solute and solution mass, free
POST /chem/mass-percent$0.002Developer Utilities
Mass percent to mole fraction calculator
free
POST /chem/mass-percent-to-mole-fraction$0.002Developer Utilities
Mass to gas volume stoichiometry calculator
product gas V from mass, free
POST /chem/mass-to-volume-gas-stoich$0.002Developer Utilities
Mixing three solutions calculator
final concentration free
POST /chem/mixing-three-solutions$0.002Developer Utilities
Mixing two solutions calculator
resulting concentration from C1 V1 + C2 V2
POST /chem/mixing-two-solutions$0.002Developer Utilities
Molality calculator
moles of solute per kg of solvent free
POST /chem/molality$0.002Developer Utilities
Molality calculator
moles of solute over kg solvent, free
POST /chem/molality-from-moles-mass$0.002Developer Utilities
Molality to molarity calculator
convert m to M with density, free
POST /chem/molality-to-molarity$0.002Developer Utilities
Molar mass calculator
formula to g/mol from atomic weights
POST /chem/molar-mass$0.002Developer Utilities
Molar mass from freezing point depression calculator
free
POST /chem/molar-mass-from-fp-depression$0.002Developer Utilities
Molar mass from osmotic pressure
van't Hoff M calculator, free
POST /chem/molar-mass-from-osmotic-pressure$0.002Developer Utilities
Molar solubility from Ksp calculator
s from Ksp and stoichiometry, free
POST /chem/molar-solubility-from-ksp$0.002Developer Utilities
Molar volume at STP calculator
ideal gas volume from moles at standard T and P, free
POST /chem/molar-volume-at-stp$0.002Developer Utilities
Molarity to mass percent calculator
M, density & MM to % w/w
POST /chem/molarity-to-mass-percent$0.002Developer Utilities
Molarity to normality calculator
N = M × equivalents per mole
POST /chem/molarity-to-normality$0.002Developer Utilities
Mole fraction calculator
x_i from component moles free
POST /chem/mole-fraction$0.002Developer Utilities
Mole fraction to molality calculator
convert x to m, free
POST /chem/mole-fraction-to-molality$0.002Developer Utilities
Mole fraction to molarity calculator
M from x, ρ free
POST /chem/mole-fraction-to-molarity$0.002Developer Utilities
Gas volume ratio calculator
stoichiometric volumes from coefficients, free
POST /chem/mole-ratio-gas-volumes$0.002Developer Utilities
Mole to mole conversion calculator
product moles from coefficients free
POST /chem/mole-to-mole-conversion$0.002Developer Utilities
Molecular formula calculator
empirical formula to molecular formula from molar mass free
POST /chem/molecular-formula$0.002Developer Utilities
Molecular formula from empirical calculator
multiplier n = M / M_emp free
POST /chem/molecular-from-empirical$0.002Developer Utilities
Moles to grams calculator
mass ↔ moles via molar mass, free
POST /chem/moles-from-mass$0.002Developer Utilities
Moles from molarity and volume calculator
n = M×V free
POST /chem/moles-from-molarity-volume$0.002Developer Utilities
Most probable molecular speed calculator
v_mp = √(2RT/M) free
POST /chem/most-probable-speed$0.002Developer Utilities
Nernst equation calculator
cell potential from E°, n, Q, free
POST /chem/nernst-equation$0.002Developer Utilities
Neutralization moles calculator
excess reagent from C and V
POST /chem/neutralization-moles$0.002Developer Utilities
Normality calculator
equivalents per liter of solution free
POST /chem/normality$0.002Developer Utilities
Normality to molarity calculator
M = N / n free
POST /chem/normality-to-molarity$0.002Developer Utilities
Number of atoms in sample calculator
N = (m/M)·N_A·n free
POST /chem/number-of-atoms-in-sample$0.002Developer Utilities
Osmolarity from osmotic pressure calculator
c = π/(RT) free
POST /chem/osmolarity-from-osmotic-pressure$0.002Developer Utilities
Osmotic pressure calculator
π = iCRT from concentration, T, and van 't Hoff factor
POST /chem/osmotic-pressure$0.002Developer Utilities
Osmotic pressure from molarity calculator
π = iMRT free
POST /chem/osmotic-pressure-from-molarity$0.002Developer Utilities
Osmotic pressure difference calculator
Δπ = (c₁−c₂)RT free
POST /chem/osmotic-pressure-two-solutions$0.002Developer Utilities
Partial pressure at new temperature calculator
p2 from p1, T1, T2 free
POST /chem/partial-pressure-change-temperature$0.002Developer Utilities
Partial pressure from mole fraction calculator
p_i = x_i·P free
POST /chem/partial-pressure-from-mole-fraction$0.002Developer Utilities
Particles to grams calculator
mass from count and molar mass, free
POST /chem/particles-to-grams$0.002Developer Utilities
Parts per thousand calculator
‰ from solute and total mass, free
POST /chem/parts-per-thousand$0.002Developer Utilities
Element percent by mass calculator
% composition from element mass and molar mass, free
POST /chem/percent-composition-element$0.002Developer Utilities
Percent dissociation calculator
% at equilibrium from C₀ and Ceq, free
POST /chem/percent-dissociation-equilibrium$0.002Developer Utilities
Percent ionization of acid calculator
% from C and Ka, free
POST /chem/percent-ionization$0.002Developer Utilities
Percent purity calculator
pure mass over sample mass, free
POST /chem/percent-purity$0.002Developer Utilities
Percent solution prep calculator
solute and solvent mass free
POST /chem/percent-solution-prep$0.002Developer Utilities
Mass percent to molarity calculator
% w/w, density & MM to M
POST /chem/percent-w-w-to-molarity$0.002