Electronics Calculator Toolbox

An electronics calculator for the workbench, and it works without a connection. Ohm's law, LED resistors, RC filters, 555 timers, PCB trace width - type a value and the answer appears as you type. No Calculate button, no sign-up. Built for people who actually solder: hobbyists and makers, ham radio operators, electronics students, anyone wiring up a microcontroller board on a breadboard, and anyone whose desk has a multimeter on it. Every calculation runs on the device, so the app keeps working in a basement lab, out in the field, or on a plane. WHAT YOU CAN WORK OUT Circuits - Ohm's law calculator - volts, amps, ohms and watts from any two values - LED resistor calculator - supply, forward voltage and current in, series resistor out, snapped to the nearest E24 value you actually have in the drawer - Voltage divider calculator, solved in both directions - RC filter calculator - cutoff frequency, low-pass and high-pass - 555 timer calculator - astable and monostable, with duty cycle - Op-amp gain, inverting and non-inverting - Zener diode regulator - Series and parallel - equivalent resistance and equivalent capacitance - Voltage drop over a long wire run - Battery life from capacity and average current draw PCB - Trace width calculator - IPC-2221, by current and temperature rise - Via current and barrel resistance - Microstrip impedance with propagation delay Converters - Number base - hex, decimal, binary - Temperature - Celsius, Fahrenheit, Kelvin - AWG to mm² wire gauge - dBm to watt Look it up - Resistor color code - an interactive 4, 5 and 6 band decoder - SMD resistor code - 3-digit, 4-digit, R-notation and EIA-96 - Capacitor code - 104 is 100 nF, plus the tolerance letters - SMD package sizes - 0402, 0603, 0805, imperial to metric ON THE BENCH - The math runs on the device - no connection needed to get an answer - Free, paid for by ads. The ads need a connection, the calculators do not - No account, no sign-up, nothing to register - Search by name, synonym or abbreviation and start typing straight away - Favorites and per-tool history, so last night's numbers are still there - Every calculator shows its formula - check the math instead of trusting a black box Whether you are sizing an LED resistor for a first breadboard build, decoding an SMD part you just desoldered, checking a trace width before the board goes out, or working out how long a coin cell will last, the calculator you need is one search away. Made by an embedded engineer who got tired of installing five apps and opening a browser tab to bring up one board.