Electrochemistry Calculator

Write your redox / cell reaction

Separate species with spaces around + and use = (or ) between sides. Write ions like Cu+2, Cr2O7-2, MnO4- (pretty Cu²⁺ works too). Balancing is checked with chempy; everything else is computed instantly.

Examples
Daniell cell Mg | Fe²⁺ dichromate + Fe²⁺ permanganate titration Cu + Ag⁺ aluminium + O₂ MnO₄⁻ + I⁻ (basic)
Standard reduction potentials (E°) reference
Half-reaction (reduction)E° (V)

Click cathode / anode to drop a value into the cell-potential fields below.

⏻ Electrolysis — Faraday's laws (mass deposited / gas evolved)

m = (Q·M)/(n·F), Q = I·t, mol e⁻ = Q/F. Molar mass M is looked up from the formula. For a gas, the volume at STP (22.414 L/mol) is shown too.

Frequently asked

Write the reaction and click Balance & analyze. chempy balances it and the tool reads each element's oxidation-state change to report n automatically. You can override n if your reaction is unusual.
cell = E°cathode − E°anode, with both values as standard reduction potentials. From E°cell the tool also gives ΔG° = −nFE° and K = e^(nFE°/RT).
Yes. Either include H⁺/H₂O (or OH⁻) yourself, or set the Auto-add option to acidic or basic and the balancer adds them.
It gives the cell potential at non-standard concentrations/temperature: E = E°cell − (RT/nF)·ln Q. Enter the species' concentrations and the tool computes Q and E.

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