Skip to content

Technology calculators

21 calculators

Download time

Estimate download duration from size and connection speed.

Bandwidth and transfer time

Estimate transfer time from data size and connection speed.

IPv4 subnet

Calculate address counts and mask information from an IPv4 prefix length.

Base64 encode and decode

Encode plain text as Base64 or decode valid Base64 text.

URL encode and decode

Percent-encode text for use in a URL component or decode it.

Screen pixel density

Calculate display pixel density and aspect ratio from resolution and diagonal size.

Image print size

Estimate print dimensions from pixel resolution and target PPI.

Capacitor stored energy

Calculate capacitor energy and signed charge from capacitance in microfarads and voltage; energy scales with voltage squared while charge is linear.

Capacitive reactance

Find the magnitude of capacitive reactance at a sinusoidal frequency; increasing frequency or capacitance lowers the opposition to alternating current.

Inductive reactance

Calculate inductive reactance using frequency and inductance in millihenries; it rises with frequency and becomes zero at direct current.

LC resonant frequency

Find the natural resonant frequency of an ideal inductor-capacitor circuit where inductive and capacitive reactance magnitudes are equal.

RC low-pass cutoff

Calculate the time constant and cutoff frequency of a first-order RC low-pass filter, whose cutoff has approximately 70.7% of the input voltage amplitude.

Wire resistance

Calculate resistance of a uniform wire from material resistivity, wire length and cross-sectional area; the area is entered in square millimetres.

Resistive voltage divider

Find the unloaded output voltage of a two-resistor voltage divider.

Two-branch current divider

Split a known total current between two parallel resistive branches.

Resistor power dissipation

Find power dissipated by a resistor from the voltage directly across it.

Inductor stored energy

Find magnetic energy stored in an ideal inductor.

Transformer reflected impedance

Reflect a secondary resistive load to the primary of an ideal transformer.

LED series resistor

Estimate a series resistor for one LED at a chosen current.

Series RLC impedance

Find impedance magnitude and signed reactance of an ideal series RLC circuit.

Sinusoidal RMS voltage

Convert the peak voltage of a zero-offset sine wave to RMS and peak-to-peak values.