Tools for people who build and buy hardware

Size the current-limiting resistor for any LED, with forward-voltage presets per colour and support for series and parallel arrays.

Decode resistor color bands to a value, or convert a value back to bands. Supports 3, 4, 5 and 6-band resistors.

Decode 3-digit ceramic capacitor codes, tolerance letters and voltage codes. 104 means 100 nF — this explains why.

Charge and discharge timing for an RC network, with the curve plotted and the 63%, 95% and 5τ points marked.

Combine any number of resistors in series or parallel — and work backwards to find the stock pair that hits your target value.

Decode 3-digit, 4-digit and EIA-96 surface-mount resistor markings, including R-notation and underlined codes.

Compute divider output voltage, or pick the best E24/E96 resistor pair for a target ratio — including the error your load introduces.

Combine capacitors in series or parallel, with working voltage and ripple-sharing notes.

Snap any ideal value to the nearest real E3–E192 part and see the error you inherit by doing so.

Decode inductor colour bands to an inductance value, with tolerance.

Estimate ripple current heating and lifetime from ESR, and see how far a capacitor's real spec sits from its label.

Design astable, monostable and 50%-duty 555 circuits. Get the schematic, the waveform, and a bill of materials in stock E24 values.

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Enter any two of voltage, current, resistance or power and get the other two, with the worked formula and a matching SPICE netlist.

Convert between dB, dBm, dBV, watts, volts and plain ratios.

Pick R1 and R2 for a target LM317 output voltage or constant-current setting, with dissipation and heatsink check.

Gain and resistor selection for inverting, non-inverting, differential, summing and instrumentation amplifier topologies.

Cutoff frequency and −3 dB response for low-pass, high-pass and band-pass filters, with a plotted Bode curve.

Duty cycle, peak switch current and component sizing for a step-up converter.

Duty cycle, inductor ripple current, output capacitor ripple and the CCM/DCM boundary for a step-down converter.

Capacitive and inductive reactance, total impedance and phase angle at a given frequency.

Resonant frequency, Q factor and bandwidth for LC tank circuits.

Gate charge, drive current, switching loss and conduction loss for a MOSFET at your switching frequency.

Size the base resistor to drive a BJT into hard saturation, using forced beta rather than the datasheet's optimistic hFE.

Bridge output voltage and balance condition, with a strain-gauge mode.

Series resistor, power dissipation and safe load range for a zener shunt regulator.

Motor current, dead-time and driver dissipation for an H-bridge stage.

Upper and lower threshold voltages and hysteresis width for inverting and non-inverting triggers.

Runtime from capacity and load — including a duty-cycled sleep profile for battery-powered IoT nodes that spend most of their life asleep.

Series/parallel cell configurations, pack voltage, watt-hours, C-rate and continuous current limits for 18650 and LiPo packs.

Minimum trace width for a target current and temperature rise, for internal and external layers, per IPC-2221.

Panel wattage and battery capacity for an off-grid or IoT node, given daily load and worst-month sun hours.

Voltage lost over a cable run, as volts and as a percentage, with a recommended gauge.

Convert AWG to mm², look up ampacity and resistance per metre, and pick a gauge for a given current and run length.

Fuse rating for a load including inrush, with I²t and fast/slow-blow guidance.

Junction temperature from dissipation and thermal resistances, and the θSA you need to stay inside the derating curve.

Characteristic impedance for microstrip, stripline and differential pairs — the geometry you need for USB, Ethernet and HDMI.

Component dissipation and the derated part rating you should actually specify.

Smoothing capacitor size for a target ripple voltage after rectification.

Turns ratio, secondary voltage and current for a mains or signal transformer.

Current a plated via can carry, and how many you need in parallel.

Convert between hex, binary, decimal, octal and ASCII, with width-aware bit grids and endianness swapping.

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AND, OR, XOR, NOT and shifts with a live bit grid so you can see exactly which bits moved.

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CRC-8, CRC-16 (CCITT, Modbus, XMODEM) and CRC-32 over hex or ASCII input, with the polynomial and shift steps explained.

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Convert between decimal, hex and binary float32/float64, with the sign, exponent and mantissa fields broken out.

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The frequency-versus-resolution trade-off made explicit, with register values for your MCU and duty-cycle counts.

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Every valid prescaler and reload pair for a target frequency on AVR, STM32, PIC and RP2040 — ranked by error, with C you can paste.

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Signed and unsigned interpretation at any register width, with overflow and carry flags.

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Register value and percentage error for any MCU clock and baud rate, with a verdict on whether the link will actually be reliable.

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Step size, ENOB, quantisation noise and SNR for a given ADC bit depth and reference voltage.

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Convert firmware blobs between base64, hex and raw bytes, with size and checksum readouts.

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Paste a C struct to see member offsets, inserted padding and total size for 32-bit and 64-bit targets — and how to reorder it smaller.

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Every valid TSEG1/TSEG2/SJW combination for your clock and bitrate, ranked by sample-point quality, with the register value.

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Solve PLL M/N/P/Q dividers for a target system clock from your crystal, respecting each stage's legal range.

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Minimum and maximum pull-up values from bus capacitance and rise-time limits, per the I²C specification.

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Build and decode Modbus RTU frames with automatic CRC, function-code reference and error decoding.

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How long your flash survives at a given write rate, and how much wear levelling buys you.

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Parse Intel HEX and Motorola SREC files, verify checksums and view the resulting memory map.

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Worst-case interrupt response from clock speed, cycle counts and priority nesting.

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Paste a register value and a field layout to get a decoded table — with presets for common STM32 and AVR registers.

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Prescaler settings to hit a target SPI clock without exceeding your peripheral's maximum.

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Estimate worst-case stack depth from call nesting, locals and interrupt frames.

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Prescaler and reload values for a target watchdog period, with the achievable timeout range.

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Quarter-wave, half-wave and dipole lengths for any frequency, with presets for 433, 868, 915 and 2400 MHz and the ham bands.

Convert frequency to wavelength and back, including velocity factor for cable and PCB.

Link budget and estimated range for LoRa, WiFi and BLE from TX power, gains and sensitivity.

Time-on-air from spreading factor, bandwidth and coding rate, with EU and US duty-cycle legality checks.

Minimum sample rate, alias frequencies and anti-alias filter requirements for a given signal.

Convert between VSWR, return loss, reflection coefficient and mismatch loss.

Bin width, frequency resolution and capture time for a given FFT size and sample rate.

Calibrate extruder steps per millimetre from a measured extrusion, with the M92 command to paste.

Steps per mm, microstepping resolution, maximum RPM and torque at speed.

Tap drill diameter and clearance hole for metric and imperial threads, at any thread engagement.

Ratio, output speed and torque multiplication for single and compound gear trains.

Pinouts for USB-A/B/C, HDMI, RJ45, DB9, JTAG/SWD, Raspberry Pi GPIO, Arduino and ESP32 — diagrammed and searchable.

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Input and output thresholds for TTL, CMOS, LVCMOS and LVDS, and which families you can safely interconnect.

Filterable comparison of common microcontrollers by core, clock, flash, RAM and peripherals — with which ones you can emulate in Chiprun.

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