# Calculators & Conversion Charts

Farnell's online conversion calculators and conversion tables provide the conversion ratios you need for your everyday calculations.

Whether you're trying to move from imperial measurements to metric, solve for Ohm's law, or make sure you've got the correct weight, these tools are designed to help.

### Capacitor Charge Calculator

Calculate time and energy needed to charge a capacitor.

Capacitor Charge Calculator### Current Divider Calculator

Calculate current flow through each of the parallel-linked resistances.

Current Divider Calculator### Fractions and Decimal

Turn any decimal value into its simplified fraction form.

Fraction - Decimal Conversion### Impedance Matching Calculator

Impedance matching allows maximum power transfer between two points.

Impedance Matching Calculator### Inductance Conversion

Turn any Inductance Conversion value into its simplified form.

Inductance Conversion### LED Series Resistor

Calculate appropriate resistance so your LEDs don't burn out prematurely.

LED Series Resistor Calculator### LM317 Resistor / Voltage calculator

Calculate output voltage of the regulator OR the value of the resistor (R2).

LM317 Resistor / Voltage calculator### Metric and Imperial

Common Metric and Imperial conversion ratios and calculator.

Metric and Imperial Conversion### Op-Amp Voltage and Gain Calculator

Op-Amp Voltage and Gain Calculator

Op-Amp Voltage and Gain Calculator### Parallel Resistance Calculator

Calculate the equivalent resistance of resistors connected in parallel.

Parallel Resistance Calculator### Passive Filter Calculator

Calculate the cut-off frequency and phase shift of a Passive RC Filter.

Passive Filter Calculator### PCB Trace Width Calculator

Calculate Printed Circuit Board Width(IPC-2221).

PCB Trace Width Calculator### Pull-up & Pull-down Resistors Calculator

Calculate the Pull-up & Pull-down resistor value.

Pull-up & Pull-down Resistors### Resistor Colour Codes

Access a convenient and standardised resistance table.

Resistor Colour Calculator### Stepper Motor

Calculate speed and time per step and max power of a stepper motor.

Stepper Motor Calculator### Temperature

For any critical temperature analysis, this calculator helps you get your job done faster.

Temperature Calculator### Transformer Turns Calculator

Calculate the primary and secondary full-load currents of the transformer.

Transformer Turns Calculator### Twisted-Pair Impedance Calculator

Calculate the characteristic impedance of a twisted-pair cable.

Twisted-Pair Impedance Calculator### Voltage Divider Calculator

Calculate output voltage of the divider circuit.

Voltage Divider Calculator### VSWR / Return Loss calculator

Compute VSWR to Return Loss and vice versa.

VSWR / Return Loss calculator### Featured content

#### Communication Network protocols

In an embedded world, communication protocols are vital in providing a gateway to reliably exchange information among various devices. Discover the collection of rules that govern this.

#### Voltage Topologies – Part 1 of 2

Switching regulators revolutionized supply methods by drastically reducing power supply limitations and miniaturizing equipment. Learn more on regulators and non-isolated DC-DC converters.

#### Voltage Topologies – Part 2 of 2

Continue exploring voltage topologies with the classifications of isolated DC-DC converters, such as flyback, forward, push-pull, half-bridge, and full-bridge converters.

#### IoT Wireless Network Protocols

Explore the latest IoT wireless protocols to assist in the selection of the right wireless network protocol for your next IoT application

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