Resistor Color Code Calculator (4-Band)

Science Tools

Read the value of a 4-band resistor

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Band 1
Band 2
Band 3 (multiplier)
Band 4 (tolerance)
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Resistor Color Code Calculator (4-Band) — at a glance

Choose the four colour bands and read the value.

Your values
Brown, Black, Red, Gold
Calculate
Result
1 kohm ±5%

How to use it — step by step

Just your input — nothing to install or sign up for.

1

Enter your values

Fill in the boxes. Sample values are already there so you can see how it works.

2

Calculate

Press the button to get your answer instantly.

3

Read the result

The main answer is shown in a large card with extra details below it.

4

Copy it

Use the copy button to save the result anywhere.

Pro tips

Small things that make the result better.

✦Hold the resistor so the gold or silver band is on the right, then read from the left.
✦The first two bands are digits, the third is the multiplier and the fourth is the tolerance.

Quick facts

Freeno signup, no limit
Instantresult in a moment
Privatenothing is uploaded
Any devicephone, tablet or PC

Frequently Asked Questions

Is my data safe?+

Yes. Everything runs inside your own browser. Your text, files and images are never uploaded to any server.

Is this tool really free?+

Yes — completely free, no signup, no watermark and no usage limit.

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