LibraTool logoLibraTool
⚡
🔋

Estimate Current Draw from a Battery

Find the current a load pulls so you can estimate battery runtime.

Prijava ni potrebna
V
A
Ω
W
Enter any two values and the other two are solved automatically

💡 Ohm's law: V = I × R. Power adds P = V × I. Knowing any two lets you derive the rest — handy for sizing resistors, checking LED current, or working out heat dissipation.

Battery tips

🔋

Enter battery voltage and the load resistance (or power) to get current draw in amps.

💡

Runtime ≈ battery capacity (Ah) ÷ current draw (A) — lower current means longer life.

🎯

Real batteries sag under load and aren't 100% efficient, so treat the runtime as an optimistic estimate.

Kako deluje

1
Vnesite
Enter your data into the tool above. Everything stays local to your browser.
2
Proces
The tool processes your data instantly in your browser using JavaScript. No server, no waiting.
3
Prenos
Get your result instantly. Nothing is stored after you leave the page — complete privacy.

Zakaj uporabljati naše?

✓Popolnoma brezplačno – brez skritih stroškov
✓Račun, e-pošta ali prijava niso potrebni
✓Datoteke nikoli ne zapustijo vaše naprave
✓Nobenih omejitev velikosti datoteke
✓Brez vodnih žigov na nobenem izpisu

Also check out…

💡

Size a Current-Limiting Resistor for an LED

Work out the resistor value an LED needs from supp

🔥

Calculate Power Dissipation (Watts)

Find how many watts a component dissipates so you

🎓

Solve Ohm's Law Homework

Check circuit problems by entering any two known v

📉

Calculate Voltage Across a Component

Find the voltage drop across a resistor from curre

Pogosto zastavljena vprašanja

Back to Ohm's Law Calculator