Which end of a resistor do I read from?

The tolerance band (usually gold, silver or brown) normally sits a little apart from the others, nearer one lead; put it on the right and read left to right. The first band can never be gold, silver or black, which also tells you the direction. The tool checks whether the reverse reading is also a valid combination — if both are, measure it with a multimeter to be sure.

What’s the difference between 4-band and 5-band resistors?

A 4-band resistor has two significant digits, a multiplier and a tolerance band; these are typically ±5% carbon-film parts from the E24 series. A 5-band resistor has three significant digits, so it can show values like 4.99 kΩ; these are usually ±1% metal-film parts from the E96 series. A 6-band resistor adds a temperature-coefficient band after the tolerance, for example brown = 100 ppm/K and red = 50 ppm/K.

What are the E12, E24 and E96 series?

They are the preferred resistor values defined in IEC 60063: 12, 24 or 96 values per decade in a geometric progression, each about 10^(1/n) times the previous one, so that the tolerance bands just overlap — E12 goes with ±10%, E24 with ±5%, E96 with ±1%. E24 runs 10, 11, 12, 13, 15 … 91. If a design calls for 4.6 kΩ, which you can’t buy, you pick the nearest standard value, 4.7 kΩ (+2.2%).

How do I read SMD codes like 472, 4702 or 01C?

In a 3-digit code the first two digits are significant and the last is the power of ten: 472 = 47 × 10² = 4.7 kΩ. In a 4-digit code the first three are significant: 4702 = 470 × 10² = 47 kΩ. The letter R marks the decimal point, so 4R7 = 4.7 Ω. EIA-96, used on 1% parts, gives the index into the E96 table plus a multiplier letter: 01C = 100 × 100 = 10 kΩ and 68X = 499 × 0.1 = 49.9 Ω. 000 is a 0 Ω jumper.

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🟫Resistor Color Code Calculator - 4/5/6 Band, Value to Colors, SMD Codes

Read and write resistor color codes following IEC 60062. Colors → value: choose 4, 5 or 6 bands, tap a band on the drawing and pick a color to get the resistance, tolerance, min and max, temperature coefficient, which E-series it belongs to and its RKM and SMD equivalents, plus a check on whether reading it from the other end is also valid. Value → colors: type 4.7k, 1M5 or 4R7 and get the nearest E6–E96 standard value with its neighbours and the band colors. The SMD tab decodes 3-digit, 4-digit, EIA-96 and R-notation codes, and generates them from a value. Every color is labelled by name for colour-blind users.

Free · No sign-up · Runs in your browserLast updated: 2026-10-26

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How to use Resistor Color Code Calculator

1Choose the number of bands (4, 5 or 6)
2Tap a band on the resistor, then pick its color to read the value, tolerance and range
3For the reverse, switch to “Value → colors”, type a value and choose a series to snap to
4For chip resistors, open “SMD codes” and type a code such as 472, 4702 or 01C

FAQ

Which end of a resistor do I read from?: The tolerance band (usually gold, silver or brown) normally sits a little apart from the others, nearer one lead; put it on the right and read left to right. The first band can never be gold, silver or black, which also tells you the direction. The tool checks whether the reverse reading is also a valid combination — if both are, measure it with a multimeter to be sure.
What’s the difference between 4-band and 5-band resistors?: A 4-band resistor has two significant digits, a multiplier and a tolerance band; these are typically ±5% carbon-film parts from the E24 series. A 5-band resistor has three significant digits, so it can show values like 4.99 kΩ; these are usually ±1% metal-film parts from the E96 series. A 6-band resistor adds a temperature-coefficient band after the tolerance, for example brown = 100 ppm/K and red = 50 ppm/K.
What are the E12, E24 and E96 series?: They are the preferred resistor values defined in IEC 60063: 12, 24 or 96 values per decade in a geometric progression, each about 10^(1/n) times the previous one, so that the tolerance bands just overlap — E12 goes with ±10%, E24 with ±5%, E96 with ±1%. E24 runs 10, 11, 12, 13, 15 … 91. If a design calls for 4.6 kΩ, which you can’t buy, you pick the nearest standard value, 4.7 kΩ (+2.2%).
How do I read SMD codes like 472, 4702 or 01C?: In a 3-digit code the first two digits are significant and the last is the power of ten: 472 = 47 × 10² = 4.7 kΩ. In a 4-digit code the first three are significant: 4702 = 470 × 10² = 47 kΩ. The letter R marks the decimal point, so 4R7 = 4.7 Ω. EIA-96, used on 1% parts, gives the index into the E96 table plus a multiplier letter: 01C = 100 × 100 = 10 kΩ and 68X = 499 × 0.1 = 49.9 Ω. 000 is a 0 Ω jumper.