Shockley Diode Calculator

The Shockley Diode Calculator solves the ideal diode equation I = Is·(e^(Vd/nVt) − 1) for any one missing variable, given the other parameters.

How to Use Shockley Diode Calculator

Choose which variable to solve — diode current I, diode voltage Vd or reverse saturation current Is.
Enter the remaining values — including ideality factor n and temperature T (kelvin).
Read the unknown — plus the thermal voltage Vt = kT/q and operating state.
Cross-check the regime — the calculator flags forward, cutoff or reverse operation.

I = Is · (e^(Vd / (n · Vt)) − 1)
Vt = k · T / q   (≈ 25.85 mV at 300 K)
Vd = n · Vt · ln(I / Is + 1)
Is = I / (e^(Vd / (n · Vt)) − 1)

Analog circuit design — model rectifiers, log amplifiers and bandgap references.
Photodiode analysis — relate output current to dark current and bias voltage.
Temperature sensing — derive Vt and its temperature drift.
Education — explore the exponential I–V characteristic of PN junctions.

Frequently asked questions about Shockley Diode Calculator

Why does the ideality factor matter?

n captures non-idealities such as recombination current. It typically ranges from 1 (ideal) to ~2 (recombination-dominated).

How does temperature affect the result?

Vt = kT/q scales linearly with temperature, and Is roughly doubles every 10 °C, so forward voltage drops with rising temperature at constant current.

Is breakdown modeled?

No. The Shockley equation describes the normal forward and small reverse regions. Avalanche or Zener breakdown require additional models.

Is my data stored?

No. All calculations run locally in your browser; nothing is sent to any server.