Electronics tools

Free tools from the repair bench - no sign-up

The tools we use on our own bench while repairing amps, speakers, TVs and power supplies. They run in your browser, work on phones, and take values the way they're printed on parts - 4.7k, 100n, 2M2.

Online tone generator

Sine, square, sawtooth or triangle from 20 Hz to 20 kHz - for testing speakers and amps and finding rattles.

Ohm's law calculator

Any two of voltage, current and resistance gives the third - and the power.

Resistor color code calculator

Colors to value for 3, 4 and 5 band resistors - or a value to its colors.

Voltage divider calculator

Any three of Vin, R1, R2 and Vout gives the fourth - feedback resistors, bias, sensing.

Electrical power calculator

Watts from any two of voltage, current and resistance - check a resistor's rating.

RC time constant calculator

Tau, charge times and the filter cutoff from a resistor and a capacitor.

Then find the part on a real board

Circuit Fixers is a library of circuit boards from real repairs, with every component marked on the photos. Search the board library for your device, look up a part in the parts catalogue, or ask about a board from your AI assistant.