Ohmbook
Every electronics formula, solved step by step.
62 formulas across 8 fields of electrical engineering. Pick what you want to find, enter what you know, and Ohmbook shows the answer along with every step of the working.
Coming soon to the App Store for iPhone and iPad.
Built for homework, the lab and the workbench
Every formula in Ohmbook is an interactive calculator, not just a reference card.
Solve for any variable
Choose the unknown and fill in the rest. Ohmbook rearranges the formula for you.
Every step shown
See the rearranged formula, the unit conversions, the substitution and the answer.
Real-world units
Tap µ, m, k or M instead of typing powers of ten. Results come back in engineering notation.
Live circuit diagrams
Schematics and graphs update as you type, so you can see what the numbers mean.
Saved and recent
Star the formulas you use most and jump back to recent ones in a tap.
Private and offline
No account, no tracking and no internet connection needed. It works anywhere.
From Ohm’s law to op-amps
Your data stays on your device
Ohmbook collects no personal data. There are no accounts, no analytics, no ads and no network connections.
Support
Found a bug, or want a formula added? Get in touch.