Ohm's Law Calculator

Use ohms law calculator to instantly find voltage and current — the fast ohms law solver, resistance calculator and more.

⚡ Ohm's Law Calculator instantly finds voltage, current, resistance and power — built for students, electricians, hobbyists and engineers who need results in seconds, not a textbook. 🚀 Quick start: 1️⃣ Click the icon to open the calculator. 2️⃣ Enter any two known values. 3️⃣ Get instant results for the other two. 4️⃣ Change units on the fly. 🔢 One tool, every variable: ➤ Resistance calculator — find R from V and I. ➤ Voltage calculator — find V from I and R. ➤ Ohms law power calculator — find P from V and I. ➤ Current calculator / amperage calculator — find I from V and R. This makes it an ohm's law current calculator and an ohm's law resistance calculator combined in a single popup — no need to switch between four separate pages to solve an ohm's law equation. 📐 Not sure which formula you need? The built-in ohms law calculator wheel — also known as an ohm's law triangle calculator — shows how the three core values relate to each other, so nothing needs to be memorized. The formulas used in your calculation are highlighted automatically. 🎨 People know this same idea by a few different names. Some call it an ohms wheel, some search for an ohm's law chart, others for ohms law chart. Whatever you call it, the visual guide is built right into the popup alongside your calculations. 🌍 Works wherever you do: - Runs the same way on Windows, Mac and Chromebook. - No internet connection required after installation. - Lightweight — won't slow down your browser. 🎓 Why people choose this tool: - Faster than calculating by hand or looking up formulas. - Works with basic Ohm's law calculations for AC and DC circuits. - No ads before you get your numbers. - No sign up, no account, nothing to configure. - A simple, free extension, right inside the browser toolbar. - Covers voltage current resistance and power without extra tabs. ⚙️ Built for real use cases: 1. Electricians double-checking resistor loads on site. 2. Students learning how to calculate ohm's law for homework and exams. 3. Makers and hobbyists sizing resistors for LED projects. 4. Engineers running a fast circuit calculator pass before a full simulation. 5. Teachers demonstrating ohms law calculations on a shared screen. 6. Electronics and audio hobbyists checking resistance before wiring components. 💡 About the math: everything here comes down to two short formulas and a few variations of them. Type any two known numbers and the ohms law calc engine calculates the other values — no need to remember which ohm's law formula calculator to reach for, and no need to check old class notes for the right ohms law formulas. 🔒 What makes it reliable: ✅ Accurate down to the decimal, every time. ✅ Works offline once installed. ✅ Clean layout, nothing competing for attention. ✅ Improved regularly based on real feedback. 📖 Frequently Asked Questions ❓ What is this extension for? 💡 It's an ohm's law solver: it works out voltage, current, resistance or power the moment two values are entered. ❓ Do I need to know how to calculate ohm's law myself? 💡 No — that's the point. Just type two numbers and let the tool do the calculating ohm's law part for you. ❓ Will it show up if I search for an ohm calculator or an ohms calculator? 💡 Yes — whether the search is ohm calculator, ohms calculator, or even ohm law calculator… ❓ Can I switch between units? 💡 Yes. You can change units anytime, and the calculator updates the results automatically. ❓ Is there a guide on how to use ohm's law calculator features like unit switching? 💡 No guide is needed — enter any two values, choose your units, and the calculator does the rest automatically. ❓ Is my data private? 💡 Yes. All calculations happen locally in your browser, and no calculation data is sent anywhere. ❓ Does it work on every website and in incognito mode? 💡 Yes, the popup behaves the same way everywhere, so it's always one click away. ❓ What if something looks wrong or a feature is missing? 💡 Feedback goes straight to the team behind this project — most requests get reviewed within a few days, and small fixes usually ship in the next update. ❓ Does it cost anything to keep using it? 💡 No hidden charges, no trial period, no upsells — it stays exactly as useful on day one hundred as it was on day one. ⚡ No more paper charts, no more juggling electrical current voltage and resistance formulas in your head. Add this ohms law calculator once, and every future calculation is one click away, right from the toolbar.