Instant SI-scaled solvers with visual resistor color-band rendering, E12 standard value matching, and 1-click launch into our live SPICE & RK4 simulators.
Interactive visual 4-band and 5-band resistor color decoder showing live painted resistor bands, exact resistance, and min/max tolerance range.
Calculate exact and nearest standard E12 current-limiting resistor values and power ratings for single or series LED strings.
Instantaneous solver for electric current, power dissipation in watts, conductance in siemens, and hourly energy consumption.
Compute divided output voltage Vout, decibel attenuation, bleeder current, and Thevenin equivalent output resistance Rth.
Compute exact parallel and series equivalent resistance for two or three resistor combinations simultaneously.
Calculate total capacitance for parallel banks and series strings along with stored coulombs Q and electrostatic energy.
Compute −3 dB corner frequency fc, time constant τ, attenuation in dB, and exact phase shift angle at any operating frequency.
Determine resonant frequency f₀, quality factor Q, −3 dB bandwidth, and damping ratio ζ (underdamped vs overdamped).
Calculate inductive time constant τ = L/R, 5τ settling time, steady-state coil current, and ½LI² stored magnetic energy.
Calculate frequency-dependent capacitive reactance Xc, inductive reactance XL, and net series reactance in ohms.
Calculate millivolt bridge output ΔV across unbalanced sensor arms and find exact null-balance resistance Rx.
Size series dropping resistor Rs, resistor wattage, and worst-case unloaded Zener diode power dissipation.
Size base resistor Rb with proper saturation overdrive margin for driving relays, motors, and high-power LEDs from 3.3V/5V GPIO pins.
Compute output clock frequency f, duty cycle %, high pulse time T_high, and low time T_low for classic NE555 astable multivibrators.
Calculate closed-loop linear gain, decibel gain, and peak output swing for both non-inverting and inverting operational amplifier topologies.
Convert linear voltage and power ratios into logarithmic decibels (20 log₁₀ vs 10 log₁₀) for audio, RF, and filter engineering.
Estimate realistic operating hours, days, and watt-hour energy storage for Li-Ion, LiPo, and lead-acid battery packs.
Calculate round-trip copper cable resistance, voltage drop percentage, delivered load voltage, and I²R wire heating.
Evaluate high-voltage flash and supercapacitor stored joules E = ½CV² and electric charge Q = CV.
Compute daily, monthly, and annual kilowatt-hour consumption and electricity cost from appliance wattage.
Exact ballistic kinematics solver supporting launch angles, initial elevation height h₀, and custom planetary gravity.
Compare classic small-angle period T₀ = 2π√(L/g) against the exact elliptic-integral nonlinear period at large release angles!
Calculate spring restoring force, elastic potential energy ½kx², natural oscillation frequency, and peak equilibrium velocity.
Solve image distance dᵢ, real vs virtual classification, linear magnification M, image height hᵢ, and optical power in diopters.
Calculate refracted ray angle θ₂, fiber-optic critical angle θc, Total Internal Reflection threshold, and phase velocity c/n.
Compute post-collision velocities v₁′ and v₂′, conserved total momentum, and dissipated kinetic energy for any restitution e ∈ [0, 1].