RL Time Constant Table: Time constant by Inductance
Reference table of time constant for RL Time Constant across a range of inductance values — exact, engine-computed figures you can read off at a glance.
RL Time Constant Calculator
Verified formula Updated Jun 2026 Private — runs on your device
Verified formula
Private
Time constant
0.005000
For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.
How to use the RL Time Constant Calculator
The RL Time Constant Calculator works out your time constant in an instant. Enter inductance and resistance and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.
- Enter the inductance.
- Enter the resistance.
- Read off your time constant — the calculator updates automatically, with no button to press.
Formula
The RL Time Constant Calculator uses the formula:
Time constant = Inductance ÷ Resistance
Worked example
For example, with inductance of 0.5 H and resistance of 100 Ω, the time constant is 0.005000.
| Inductance | 0.5 H |
|---|---|
| Resistance | 100 Ω |
| Time constant | 0.005000 |
|---|
Results are estimates for educational use, not professional advice.
Frequently asked questions
Divide inductance by resistance: τ = L ÷ R. A 0.5 H inductor with 100 Ω has a time constant of 0.005 s.
It is the time for the current to reach about 63% of its final value when changing.
After about five time constants the current is within 1% of its final steady value.
An RC time constant is R × C, while an RL time constant is L ÷ R; both describe exponential change.
Enter the inductance. Enter the resistance. Read off your time constant — the calculator updates automatically, with no button to press.
Related guides
How to Calculate RL Time Constant: Formula, Steps & Examples
Learn how to calculate RL Time Constant — the formula explained step by step, with worked examples and a free calculator to check your answer.