Resistance Converter

Last updated: June 2026

Resistance value

ohm

From unit

Ohms

1,000 Ohm

Milliohms

1,000,000 mOhm

Kilohms

1 kOhm

Megaohms

0.001 MOhm

Gigaohms

1.0000e-6 GOhm

4-band resistor colour decoder

Band 1Band 2MultiplierTolerance

Decoded resistance

1 kOhm +/- 5%

Formula

1 kOhm = 1,000 Ohm. 1 MOhm = 1,000,000 Ohm. 1 GOhm = 1,000,000,000 Ohm. 1 mOhm = 0.001 Ohm. For 4-band resistors, value = first two digits x multiplier, with the fourth band giving tolerance.

Common resistor values

Value	Equivalent
1 Ohm	0.001 kOhm
10 Ohm	0.01 kOhm
100 Ohm	0.1 kOhm
1 kOhm	1,000 Ohm
10 kOhm	10,000 Ohm
100 kOhm	0.1 MOhm
1 MOhm	1,000 kOhm

About this calculator

Resistance Converter helps you convert ohms, milliohms, kilohms, megaohms, or gigaohms to equivalent resistance units and 4-band resistor colour value quickly without doing the arithmetic by hand. It is designed for everyday checks where a clear answer matters: electronics repair, resistor colour decoding, Ohm unit conversion, breadboard and circuit checks. Enter a number in either side of the converter, use the swap button when you want to reverse direction, then compare the result with the quick reference table. Measured resistance can differ from the colour-code value because of tolerance, temperature, component age, and whether the resistor is measured in-circuit.

Resistance Converter formula

The calculator applies a fixed unit conversion factor. For bidirectional conversion, the reverse formula uses the same factor in the opposite direction.

1 kOhm = 1,000 Ohm; 1 MOhm = 1,000,000 Ohm; 1 GOhm = 1,000,000,000 Ohm
4-band resistor value = first two colour digits x multiplier, with the fourth band giving tolerance

How to use the resistance converter

Type the ohms, milliohms, kilohms, megaohms, or gigaohms value into the first input.
Read the converted equivalent resistance units and 4-band resistor colour value value in the second input.
Type into the second input if you want to convert in the opposite direction.
Use the swap button to change which unit appears first.
Check the formula display if you need to show your working.
Use the reference table for common values without repeated typing.

Worked examples

Example conversion

Input: 4.7 kOhm

Calculation: 4.7 kOhm = 4.7 x 1,000 = 4,700 Ohm

Result: 4,700 Ohm

Second example

Input: Brown black red gold

Calculation: Brown black red gold = 10 x 100 = 1,000 Ohm +/- 5%

Result: 1,000 Ohm +/- 5%

When this conversion is useful

Use this converter when information is given in ohms, milliohms, kilohms, megaohms, or gigaohms but your form, plan, recipe, product listing, or comparison needs equivalent resistance units and 4-band resistor colour value. It is especially useful when mixing UK, metric, and imperial measurements.

Electronics repair: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.
Resistor colour decoding: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.
Ohm unit conversion: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.
Breadboard and circuit checks: Enter the source value, check the converted result, and keep enough decimal places for the level of precision needed.

Rounding and precision

The live converter keeps useful decimal precision, while the reference table rounds values for readability. For casual use, rounded values are usually enough. For engineering, legal documents, medical records, building work, or purchase specifications, keep the original units and confirm the required precision before relying on a rounded number.

Common mistakes

Rounding too early and then using the rounded number in another calculation.
Mixing UK imperial and US customary units where they are not the same.
Entering a combined value in one field when the calculator expects separate units.
Copying a result without the unit label.
Using an approximate mental conversion when an exact factor is needed.

Conversion disclaimer

This converter is for general information and everyday calculation support. It does not replace professional measurement, medical, engineering, legal, or product-specific guidance where exact tolerances matter.

Reference table values may be rounded.
Source measurements can be approximate before they reach the calculator.
Some industries require specific rounding rules or certified measuring equipment.

Frequently asked questions

What is the formula for the resistance converter?

Use 1 kOhm = 1,000 Ohm; 1 MOhm = 1,000,000 Ohm; 1 GOhm = 1,000,000,000 Ohm. To convert back, use 4-band resistor value = first two colour digits x multiplier, with the fourth band giving tolerance.

Can I type in either input?

Yes. The converter is bidirectional, so changing either input updates the other side.

Why does my result have decimals?

Many unit conversions do not produce a whole number. Decimals keep the result more accurate than rounding to the nearest whole unit.

Should I round the answer?

For everyday use, rounding to one or two decimals is often fine. For technical work, keep more decimal places and follow the rounding rule required for that task.

Are UK and US units always the same?

No. Some units, especially gallons and fluid ounces, differ between UK imperial and US customary systems. Use the converter that matches the system you need.

Related calculators

Ohm's Law Calculator
Series Resistor Calculator
Parallel Resistor Calculator

What does this mean?

This calculator is designed to help you understand the likely number before you make a decision or start an application.

Your result should be checked against official UK guidance, especially if your circumstances include dependants, exemptions, prior leave, or a complex immigration history.

Treat the figure as a planning tool rather than legal advice. Where the answer affects an application deadline or major payment, speak to an authorised adviser.