Most people learn the resistor color code twice: once from a mnemonic for a test, and again, properly, after squinting at a bag of mixed resistors for the tenth time. This guide tries to get you to the second stage directly. It starts with the sequence itself, gives several mnemonics so you can pick one that you will actually remember, shows the patterns that make the multiplier band almost automatic, and ends with a graded practice set. If you only need the table, the printable color code chart has everything on one page.
The sequence you need to remember
The whole code rests on one ordered list of ten colors, each standing for a digit:
| Digit | Color | Memory hook |
|---|---|---|
| 0 | Black | Nothing, darkness — zero |
| 1 | Brown | One step up from black |
| 2 | Red | Start of the rainbow |
| 3 | Orange | Rainbow |
| 4 | Yellow | Rainbow |
| 5 | Green | Rainbow |
| 6 | Blue | Rainbow |
| 7 | Violet | End of the rainbow |
| 8 | Grey | Almost white |
| 9 | White | Everything, brightest — nine |
Look at the middle six. Red, orange, yellow, green, blue, violet is the rainbow in order, the same sequence most people learned as "ROY G BIV" with indigo dropped. So you do not really have ten colors to learn: you have a rainbow from 2 to 7, plus two dark colors at the bottom (black 0, brown 1) and two light colors at the top (grey 8, white 9). The ends run from darkest to lightest, which is easy to reason out even if you forget the details.
Mnemonics: pick one and say it out loud
A mnemonic is a sentence whose word initials follow the color order. The classic version taught in schools and in older textbooks has a long history of crude variations that you will still find online; the cleaner alternatives below work just as well.
- Better Be Right Or Your Great Big Venture Goes Wrong — the most common clean version, and the one used across this site.
- Bad Beer Rots Our Young Guts But Vodka Goes Well — popular with university students.
- Big Brown Rabbits Often Yield Great Big Vocal Groans When Gingerly Slapped — the long form adds gold and silver at the end.
- Make your own. A sentence about your own hobby, team or pet is far easier to recall than someone else's, and the rule is simple: ten words, starting with B, B, R, O, Y, G, B, V, G, W.
The weak point of every mnemonic is the three B words and the two G words. "B" could be black, brown or blue, and "G" could be green or grey. The rainbow trick fixes that: the B in the rainbow (position 6) is blue, so the two B words at the start are black then brown, dark before less dark. The G inside the rainbow (position 5) is green, so the G near the end is grey. If you remember that the mnemonic only hands you the first letter and the rainbow tells you which color it is, you will not mix them up.
The multiplier band is just "add zeros"
On a 4-band resistor the third band is the multiplier, and it uses the same digit colors. A multiplier color with digit N means "write N zeros after the first two digits". That turns the multiplier into a counting exercise instead of a second table to memorise:
- Brown (1): one zero. Red, red, brown = 22 + 0 = 220 Ω.
- Red (2): two zeros. Yellow, violet, red = 47 + 00 = 4,700 Ω = 4.7 kΩ.
- Orange (3): three zeros, which is exactly kilohms. Brown, black, orange = 10 kΩ.
- Yellow (4): four zeros, so tens of kilohms. Brown, black, yellow = 100 kΩ.
- Green (5): five zeros, hundreds of kilohms. Blue (6): six zeros, megohms.
The handy anchors are orange = kΩ and blue = MΩ. With those two fixed, red is "hundreds of ohms to a few kilohms" and yellow is "tens of kilohms". Gold and silver as multipliers divide instead: gold ×0.1, silver ×0.01, so yellow, violet, gold is 4.7 Ω. Gold and silver are never digits, which also tells you which end of the resistor to start reading from.
Tolerance: only four colors matter
You do not need the whole tolerance column. In practice you meet gold (±5%) on beige carbon-film resistors from hobby kits, brown (±1%) on blue metal-film resistors, silver (±10%) on older parts, and no band at all (±20%) on very old ones. A useful link: the brown tolerance band means ±1%, and brown is also the digit 1. Red tolerance is ±2%, matching red's digit 2. The full chart lists the rarer bands such as green (±0.5%) and violet (±0.1%).
Recognise common resistors on sight
The fastest readers do not decode at all for the values they meet every day; they recognise the pattern. Learn these five and you have covered a large share of the resistors used in beginner projects:
| Bands (4-band) | Value | Typical job |
|---|---|---|
| Red, red, brown | 220 Ω | LED resistor on 5 V |
| Orange, orange, brown | 330 Ω | LED resistor, signal series resistor |
| Brown, black, red | 1 kΩ | Transistor base, dim LED |
| Yellow, violet, red | 4.7 kΩ | I²C pull-up |
| Brown, black, orange | 10 kΩ | Pull-up, pull-down, divider |
Notice that 1 kΩ and 10 kΩ share brown, black; only the multiplier changes from red to orange. This is the most common misread in kits, so look at the third band twice.
Practice: from easy to tricky
Memory sticks through retrieval, not rereading. Cover the answers, read each code, then check. Work through the set once a day for three or four days and the code becomes automatic.
Level 1: 4-band, everyday values
- Brown, green, red, gold
- Red, violet, orange, gold
- Green, blue, brown, gold
- Grey, red, red, gold
Answers: 1) 15 + 00 = 1.5 kΩ ±5%. 2) 27 + 000 = 27 kΩ. 3) 56 + 0 = 560 Ω. 4) 82 + 00 = 8.2 kΩ.
Level 2: gold and silver multipliers
- Orange, white, gold, gold
- Red, red, silver, gold
- Brown, black, black, gold
Answers: 1) 39 × 0.1 = 3.9 Ω. 2) 22 × 0.01 = 0.22 Ω, a current-sense value. 3) 10 × 1 = 10 Ω; black as a multiplier adds no zeros.
Level 3: 5-band precision resistors
- Brown, black, black, red, brown
- Yellow, white, white, brown, brown
- Red, red, black, black, brown
Answers: 1) 100 + 00 = 10 kΩ ±1%. 2) 499 + 0 = 4.99 kΩ ±1%. 3) 220 with no zeros = 220 Ω ±1%. On 5-band parts the multiplier is one step lower than on the 4-band version of the same value, because the third digit has taken one of the zeros.
Habits that prevent mistakes
- Read under white light. Red, orange and brown look alike under warm bulbs, and violet and blue under cool LEDs. Daylight or a neutral bench lamp helps more than squinting.
- Find the end first. Gold or silver goes on the right. On 5-band blue resistors, the tolerance band is often set slightly apart.
- Sanity-check against the E-series. Real resistors come in standard values. If your reading gives 34 kΩ on a ±5% part, you are probably reading it backwards: 34 is not an E24 value, but 43 is.
- Confirm with a meter when it matters. A multimeter settles a faded or burnt band in seconds.
When you want to check yourself, the resistor color code calculator decodes any combination and also works backwards from a value to its colors, which makes a good self-quiz: type a value, guess the bands, then look. For the full reading procedure including 6-band parts, see how to read resistor color codes.