RF & Electronics Calculator Hub

Microstrip Impedance

Calculate microstrip transmission line impedance using Hammerstad-Jensen equations. Get Z₀, effective dielectric constant, and propagation delay for PCB trace design.

Link Budget

Calculate RF link budget: transmit power, free space path loss, antenna gains, and received signal level. Determine link margin and maximum range.

VSWR / Return Loss

Convert between VSWR, return loss, reflection coefficient, mismatch loss, and reflected/transmitted power percentage for RF impedance matching.

dBm Converter

Convert dBm to watts, milliwatts, dBW, dBμV, and volts RMS. Essential RF power unit conversion tool for signal levels and link budgets.

Cascaded NF

Calculate cascaded noise figure for a chain of RF stages using the Friis formula. Essential for LNA and receiver chain design.

Skin Depth

Calculate the skin depth (penetration depth) of electromagnetic fields in conductors as a function of frequency and material properties.

Wavelength / Frequency

Convert between frequency, wavelength, and wave number in free space or medium. Calculate half-wave and quarter-wave lengths for antenna and transmission line design.

Coax Impedance

Calculate coaxial cable characteristic impedance, capacitance, inductance per unit length, and cutoff frequency from inner/outer conductor dimensions and dielectric.

Attenuator Designer

Design Pi (π) and T attenuator pads for any attenuation value and impedance. Returns standard resistor values for both topologies with nearest E24 values.

Trace Width

Calculate minimum PCB trace width for a given current, copper weight, and temperature rise per IPC-2221 and IPC-2152 standards. Includes resistance and voltage drop.

Trace Resistance

Calculate PCB copper trace DC resistance from width, length, thickness, and temperature. Includes sheet resistance and temperature coefficient.

Differential Pair

Calculate differential (Zdiff) and common-mode (Zcom) impedance for edge-coupled microstrip differential pairs used in USB, HDMI, Ethernet, and high-speed serial interfaces.

Via Calculator

Calculate PCB via impedance, capacitance, inductance, current capacity, aspect ratio, and DFM warnings. Covers through-hole and blind/buried vias.

Stackup Builder

Calculate characteristic impedance for common PCB stackup configurations. Select layer count, dielectric thickness, and copper weight to get target trace width for 50Ω or custom impedance.

Voltage Divider

Calculate voltage divider output voltage, current, Thévenin impedance, and power dissipation from Vin, R1, and R2. Ideal for bias networks and level shifting.

LED Resistor

Calculate the correct current limiting resistor for an LED. Shows exact value, nearest E24 standard, actual current, and power dissipation.

Buck Converter

Design a synchronous buck (step-down) converter: calculate duty cycle, inductor value, output capacitor, input capacitor, and theoretical efficiency.

LDO Thermal

Calculate LDO regulator power dissipation, junction temperature, thermal margin, and minimum dropout voltage for thermal design validation.

Battery Life

Estimate battery runtime for IoT and portable devices given average current draw, duty cycle, self-discharge rate, and depth-of-discharge cutoff. Suitable for LiPo, alkaline, NiMH, and coin-cell batteries.

Filter Designer

Design passive RC and LC Butterworth low-pass, high-pass, and band-pass filters. Calculates component values (C, L), time constant, and attenuation for filter orders 1 through 4.

Nyquist Sampling

Calculate Nyquist sampling rate, oversampling ratio, aliasing frequency, ADC dynamic range, SNR, and data rate. Verify that your sampling rate satisfies the Nyquist criterion and avoid aliasing in your system.

Dipole Antenna

Calculate the physical length, wavelength, gain, radiation resistance, and 50Ω VSWR for a half-wave dipole antenna at any frequency. Supports velocity factor for insulated wire.

Patch Antenna

Calculate rectangular microstrip patch antenna dimensions (width, length) using the Transmission Line Model. Outputs effective dielectric constant, edge-feed impedance, and nominal gain for common substrates like FR4 and Rogers.

EIRP / ERP

Calculate Effective Isotropic Radiated Power (EIRP) and ERP from transmit power, cable loss, and antenna gain. Check compliance against FCC, ETSI, and ISM-band regulatory limits.

Ohm's Law

Calculate voltage, current, resistance, and power using Ohm's Law. Enter any two values to solve for the remaining two quantities.

Color Code

Decode resistor color bands to resistance value and tolerance. Supports 4-band, 5-band, and 6-band resistors. Instant color band to ohms conversion.

RC Time Constant

Calculate RC circuit time constant τ, charge time to 63.2% and 99%, and −3dB cutoff frequency. Essential for filter and timing circuit design.

Series/Parallel R·C·L

Calculate the equivalent series and parallel combination of up to four resistors, capacitors, or inductors. Also computes the voltage divider ratio for two-resistor networks.

LC Resonance

Calculate the resonant frequency, characteristic impedance, Q factor, and bandwidth of a series or parallel LC tank circuit. Enter inductance, capacitance, and optional series resistance.

Op-Amp Gain

Calculate op-amp voltage gain, gain in dB, −3 dB bandwidth, and input impedance for inverting, non-inverting, and differential amplifier configurations.

UART Baud Rate

Calculate UART frame timing, throughput, and USART BRR register divisor from baud rate, data format, and MCU clock frequency. Identify baud rate error for reliable serial communication.

I2C Pull-Up

Calculate I2C pull-up resistor values for Standard (100 kHz), Fast (400 kHz), and Fast-Plus (1 MHz) modes. Derives minimum, maximum, and recommended resistance from supply voltage and bus capacitance per NXP UM10204.