Ohm's law
Calculate voltage, current, resistance and power from two known values.
Runs locally in your browser
Electronics calculated and organised
20 calculators, a local component inventory, BOM and project journal — no account and no server upload.
Common tasks
LED series resistor
Choose an LED current-limiting resistor and check its minimum power rating.
Battery runtime
Estimate runtime from battery capacity, load current and system efficiency.
Component inventory
A private parts catalogue with quantity, location, filters, import and export.
BOM calculator
Build project bills of materials, calculate cost and export data.
Project journal
Save goals, notes, status and project checklists locally in the browser.
Your workshop in one place
Each calculator links to explanations, and results can feed your local project and BOM workflow.
Electronics calculators
Fast calculations for circuits, components, power and signals.
Project workspace
Local component inventory, BOM and project journal.
Component reference
Practical selection and use of common electronic parts.
Workshop guides
From first measurements to moving a prototype onto a PCB.
Troubleshooting
Structured fault-finding instead of random part replacement.
Safety and methodology
Units, formulas, assumptions and safe power-up.
✓
Private by design
Calculations run on your device. Inventory, BOM and projects stay in localStorage until you export or delete them.