Re-imagining The Resistor Color Code Cheat Sheet

Some people look at a venerable resource like resistor color code charts and see something tried and true, but to [Andrew Jeddeloh], there’s room for improvement. A search for a more intuitive way is what led to his alternate cheat sheet for resistor color codes.

Color code references typically have a reader think of a 560 kΩ resistor as 56 * 10 kΩ, but to [Andrew], that’s not as simple as it could be. He suggests that it makes more sense for a user to start with looking up the colors to make 5.6 (green-blue), then simply look up that a following yellow band means resistance in the 100 kΩ range (assuming a four-band resistor); therefore 560 kΩ is green-blue-yellow.

The big difference is that the user is asked to approach 560 kΩ not as 56 * 10 kΩ, but as 5.6 * 100 kΩ. [Andrew] shares a prototype of a new kind of chart in his post, so if you have a few minutes, take it for a spin and see what you think.

Is his proposed method more intuitive, or less? We think [Andrew] makes a pretty good case, but you be the judge. After all, just because something has always been so doesn’t mean there isn’t room for improvement. This happens to apply nicely to resistors themselves, in fact. It may seem like through-hole resistors have always had color bands, but that is not the case.

107 thoughts on “Re-imagining The Resistor Color Code Cheat Sheet

  1. Personally I think resistor manufacturers should just silk screen on the value in text.
    Silk screening isn’t all that expensive, and much more readable than bands of color.

    After all, if they can do it on a 0603 resistor and bellow, why not a through hole one too? Its round nature shouldn’t matter much, since they already do it on practically all through hole diodes.

    1. There are resistors with printed values.

      The values inevitably end up under the installed part where you can’t read it. You can’t readily check a finished board to see if the parts are in the right place.

      Flat SMD resistors are all placed with the printed values up.

      1. The idea of the number inevitably ending up the wrong way around and facing the board or other hard to see areas isn’t that hard to fix.

        An easy solution is to print the number three times 120 degrees apart.

        And this shouldn’t be hard since yet again, diodes usually have their names wrapped around the whole package.

        Though, the markings on components in general could likely be better, there is far too many components with frankly illegible text on them…

          1. Well, a lot of modern markings on chips are just laser engraved, no paint in sight, just charred plastic for better or worse.

            Perhaps some other pigment in the plastic might aid the text clarity to be fair, though I guess people would be surprised if the chip were a different color.

        1. They are cylindrical because of the way they are rotated through powdered resin and then heated to melt it. Anything else means molding, which is more expensive and offers no other advantage for a thru hole part.

      1. Not really clever, since the colors were chosen so badly that color vision deficiency makes it impossible to decode.
        They should have used something like a bar code instead.

          1. Yes, they would have had to invent barcodes first.

            If colir codes are a problem, wait till Hackaday does a story about early resistors and how there were a lot more values until a reset made it simpler. People working on old radios get confused by the “non-standard” values they find.

            I wouldn’t be surprised if you go back far enough that different companies had different value resistors.

            I once bought a bag of 1.1K resistors really cheap. So I’d usebthem instead of 1K. Kind of a signature.

        1. The color code works quite well. I can read them (usually) but am completely unable to read bar codes.
          Sometimes now a flashlight is needed to get better color resolution and the other trick I use is my phone camera on macro setting to take a closeup picture.
          Maybe it is just that I have been reading resistors for a lot of years?
          But we really do not need yet another standard.
          Although “they” do say, “Standards as so good, that is why we have so many of them !”

    2. Believe it or not, but there were times (40s? 50s?) when resistors had human readable text.
      Not just numbers, but the full values.
      Say, “4,7 KOhm”. Just like electrolytic caps still have. Then came industrialization and mass production around and *poof* we forcefully got the color codes instead.

      1. I’ve never seen that, and yes, I’ve looked inside tube gear.

        The only time I’ve seen values printed on resistors were low wattage precisiin resistors.

        1. Hello. The type of Resistors I mean are from Europe, I suppose. And Japan, maybe.
          My father still has a couple of them in his possession.
          No idea how popular they were in English speaking countries. 🤷‍♂️

          Here’s a picture:

          Searching for manufacturers like Rosenthal, Hoges etc bring up some pictures, as well. Some high current models seem still to be made, which I haven’t expected, also.

          vy73s/55s, Joshua

          1. Power resistors got printed labels as far back as I can remember (I’m 63 and started playing with electronics in the ‘60s). Smaller devices got color codes. Even molded capacitors from the 40s-50s got colored dots.

      1. That’s why color codes were invented in first place, I think. So that stupid machines can read the values with a photodiode etc and don’t grab the wrong parts. .
        They surely were not introduced to make people’s life easier.
        A human perhaps wouldn’t make sure they look upwards all the time,
        but at least take care that the letters/numbers wouldn’t face to PCB side.

        1. I’m pretty sure color codes came well before the ability of machines to read them. I remember seeing capacitors in old computers that had six colored dots to indicate their value, and they came from a machine that used 8″ disk drives and a dumb terminal.

    3. And while they were at it, they could start printing the value on SMD capacitors.
      It really annoys me that the value is printed on the resistors and not on the capacitors for some reason.

      1. It is interesting how capacitors have largely been left out of the labeling game. Though, the square nature of SMD capacitors makes rotating them a bit easier, unlike the flatter resistors.

        However, some capacitors are flatter and could have text on them without rolling them being an issue.

        I have though also noticed how a lot of SMD inductors aren’t labeled either.

    4. I’ve learned the color code as a kid by association, 33 is orange-orange 47 is yellow-violet etc. It’s second nature, even the multiplier comes to me without effort. Too bad it’s pretty much useless – I’m not an EE and don’t have much interest in DIY recently.

    1. Two problems with your method: You often can’t test the resistance of a resistor without unsoldering one end to isolate it from the circuit and you need the bands to know if the measured resistance is the correct resistance.

  2. “Color code references typically have a reader think of a 560 kΩ resistor as 56 * 10 kΩ… The big difference is that the user is asked to approach 560 kΩ not as 56 * 10 kΩ, but as 5.6 * 100 kΩ”

    I just think of the multiplier band as the number 0s. In the example it is 56 and four 0s. If you can’t easily mentally convert that into k or M you will have problems doing electronics.

      1. 40 years of doing electronics, and I never clocked that there was any other way of thinking about the the multiplier!

        I find this the fascinating aspect to this HaD article.

    1. BT: 110% in agreeance.
      …and I just assumed that *everyone* was taught/learnt this way too, and that there was no other method.
      (Was nine when my old man taught me)
      Red = two zero’s
      Org = three
      Ylw = four.

      The proposed method just seems *way* harder.

      1. Except that the proposed method is consistent with ‘scientific notation,’ which is commonly used when dealing with large numbers and ranges of orders of magnitude. Moreover, the current system means the same resistor value has two different color codes – one four-band code and one five-band code, which could have been eliminated if a scientific-notation approach had been adopted initially.

        Personally, I have such trouble differentiating some of the colors on the small bands (particularly on tiny 1/8W resistors) that I just use my multimeter.

    2. Right on. Especially helpful to remember this when you get these 1% resistors with three digit bands before the multiplier. If you’re used to seeing 4700 ohms as yellow purple red, from dealing with 5% resistors, it’s kind of strange to discover it’s yellow purple black brown in your 1% kit.

      (Side rant – using brown for the tolerance band is .. intolerable, when they make it the same width and space it the same as the other bands. Which end do you start reading from? A wider gap before the tolerance band, or a wider tolerance band, or make it dashed, would vastly improve matters)

      1. The four-band precision resistors I’ve seen tended to have the first band closer to the end of the resistor as well as it being a wider stripe. Usually easier to tell, but I’ll admit some were hard to determine, like you pointed out.

        Now, having wide variations in colors between manufacturers (dark red versus bold red) is one of my pet peeves!

    3. Same with me, and after some 30 years of playing with resistors I’d have a very hard time adapting to alternate method described in the article.

      It might have been a good idea if this was proposed when color banded resistors were starting to get produced but after a few decades? It feels like someone’s fixing the barn door after the horses left.

  3. It took me years to remember the colour codes for resistors, because I usually need to see patterns to remember something.

    So, here’s the pattern for resistors.

    Firstly, the outer pattern: monochrome, colour-wheel, monochrome.

    So, it’s quite easy to remember black, brown (leading into the colours), colours, grey, white.

    The colours are just most of the basic hues going round a colour wheel starting with red:

    Red, Orange, Yellow, Green, Blue, Purple.

    However, there’s an extra colour between Red and Yellow (Orange), and Cyan is missing.

    This gives us all of them:

    Black=0, Brown=1, [ Red=2, Orange=3, Yellow=4, Green=5, Blue=6, Purple=7], Grey=8, White=9.

  4. Most resistors are 1% now, and the bands are basically unreadable on a blue background. So I just gave up. If it’s still in its bag, I read the bag. If it’s on my bench, I use a meter. If it’s in-circuit, I’m SOL since not even a cheat sheet will help.

  5. I never had problems reading 5% resistors. No chart necessary. Manufacturers have apparently gone out of their way to ensure that the colors and spacing on 1% resistors are essentially unreadable and a chart will not help. Can’t even tell which end to start reading from. Need a simple talking component identifier.

  6. I have worked with electronics for nearly 60 years and have to say that I recognize all E12 and most E24 values on sight just by their 4 band colour patterns (even though I am partially colour blind).
    The first 2 band are a value between 1.0 and 9.1. The third band tells me the range e.g. if red it will be Ks, orange it will be 10Ks etc. (note the power of ten offset versus the colour’s value). The tolerance band is used to orientate the pattern to allow it to be recognised. Of course, 2% tolerance resistors occasionally give 2 possibilities. Then it’s up to a multimeter to verify which is the correct value.
    This long-used approach appears to be conceptually similar to the “new” method proposed but doesn’t need a chart.

  7. Interesting the way that people think/ are taught/ remember.
    When I first learned the colours (when 20% tolerances were common!) I would read Red Red Red as “2,2, 2 noughts”.
    Soon enough I just remembered that a Red band 3 was k ohm and Green band 3 was M ohm – the mental jump for the intermediate colours wasn’t too difficult.
    It seems to me that this “problem” has arisen because band 3 is no longer the number of noughts so my initial method would fail but my second still works once I’ve recognised that it is a 1% resistor!

  8. One important thing is there’s a whole industry around decoding color codes, and beginners buy into it. The whole mnemonic thing, to remember the color sequence is like trying to send morse code by looking up the character first. Radio Shack used to sell a decoder wheel. The problem is, I think these things make beginners think the process harder than it is.

    I can’t remember my thought process 51 years ago. I guess I looked up the first resistors on a chart. But soon I was buying “computer boards” (no ICs just transistors) and sfripping them. I just memorized the color code by looking up colors on the color code chart in the ARRL Handbook. Nobody taught me, I didn’t think it out, it was just part of it all. I don’t have a method, I look at a resistor and know.

    We didn’t have DMMs back then, so checking on an analog meter took more effort than reading the color code. And if you use a DMM, you’ll never learn the code. There are good reasons to check, in case the resistor is out of spec or marked wrong, but that’s different.

    Beginners shouldn’t stay as beginners. There’s a big world beyond.

  9. This is how I do it:
    Because resistors are mostly exponential, (and maybe engineer preferences) the lowest colors are used most, and they go from dark to bright yellow. (Remember, that Brown is just a dark orange

    So then you already have Black / Brown / Red / Orange / Yellow. With those colors you’ve already got most of the resistors.

    You can’t have much brighter colors then Yellow, so it follows the rainbow for a while (In reverse, we started at black) and you can add Green / Blue / Violet.

    After that they’ve run out of colors, so they add Grey and white for the final numbers.

    But numbers are not enough, so they added some metals for the extra things.

    And once you’ve sorted a bag of a few hundred resistors (for example cleaned out some breadboards) then you will never forget again that 2k2 and 33k are the blandest resistors of them all.

    1. “So then you already have Black / Brown / Red / Orange / Yellow. With those colors you’ve already got most of the resistors.”
      Precisely the issue. They use the colors of color vision tests with low contrast.
      “Awesome” design”

  10. I went to DeVry institute in the late 90’s. I am red green brown color weak and the tiny little resistors are really hard to distinguish bands on. I quickly learned to just use a meter on anything not in circuit and to ask for help with anything in circuit. Good magnification can also help significantly. Good natural lighting also helps alot.

    1. I went to a technical high school and learned electronics there. And I am also red-green color blind and had a hell of time learning the color code. The color bands are really not made for people like us. Meter’s for the win.

    2. You can measure resistors directly in the circuit.
      There can be “stuff” in parallel, but this can only make the resistance smaller, and never bigger.

      I’m guessing you can meause about half to 3/4 of the resistors in a circuit in this way.

      Webcams can recognise texts and overlay them with translations these days without too much trouble.

      It can’t be too difficult to have a bit of image recognition for the colors and print them in numbers, or directly translate them to a resistor value.

      1. How does the AI tell which end is which, when the manufacturer makes all the bands the same width and spacing and symmetrically centers them on the resistor body? Is it 120 ohms brown red black black brown, or is it 10k brown black black red brown?

  11. Although it is somewhat limited in value with smd resistors, the *only* way to learn the resistor color code is as follows and it takes maybe 3 or 4 hours and it will last you for a lifetime:
    Buy an assortment of 1/8 watt resistors, maybe 300 of them and if they are all grouped together with tape, cut them apart where they are all loose.
    Dump them onto the table.
    Set aside an hour for each session.
    Sort them all by value. Not by colors.
    Scramble them up again and sort them again. Rinse and wash again and again.
    After you do this for about 4 sessions you will develop a hardwired sense of automatically identifying the values by sight and it will stick with you. It will give you the ability to look at a circuit board and know at a glance the values of *all* of the resistors instantly which is a pretty cool trick. There is something about this that is like riding a bike that it stays with you.
    Otherwise it’s using a chart which you won’t always have or counting against the memory aid Bad Boys R(avage) Our Young Girls But Violet Gives Willingly. (Sorry, politically incorrect but old school).
    You could always tell a rank novice where they would be talking to themselves and counting on their fingers, taking 2 minutes to identify a single resistor where Master Foo knew all the resistors on the circuit board instantly at a glance.
    Which would you prefer to be?

      1. I’d say contrast was better decades ago. And yet there were those mnemonics and Radio Shack decoder rings.

        Reading color code is like being able to understand a schematic, or get some information by looking at a board. It’s not something you start with, and it may seem beyond you, but it all cones from knowing more and more about electronics.

        There’s a much bigger space between beginner and mediocre than between mediocre and advanced.

    1. That’s exactly how I learned them in the 50’s, except I didn’t buy the resistors. I had a cigar box full of them salvaged from broken equipment. I’d pick one out randomly and read it. I can still read them at a glance.

      1. My first task in my first real job was to unsolder the resistors on a load of old boards and put them in the correct drawers for re-use. By the end of the first week I knew how to unsolder components without damaging them and knew the colour code by heart. 50 years later I still have those skills, so 1 week from 2600 wasn’t too great an investment of my time. Nowadays I would have more difficulty remembering where I had put the look-up chart than remembering the code.

  12. BTW. I work with dozens of other electrical engineers and there isn’t one who is under 40 that you could hand a 1.2k resistor who can identify it without a chart but each and every one of the old fart radio guys can do it instantly. I guess it’s a lost art.

  13. In the politically incorrect late 90’s when I learned the color code it was memorized with the saying ” bad boys rape our young girls but violet gives willingly”. It works and you don’t forget it!

  14. I use one of these cardboard things with rotating color wheels (dont know what they are called but I guess you all know them). For me this works way faster than grabbing my multimeter, setting it to the /expected/ range, applying the probes, noticing that the value is out of range, resetting the range, probing again… As a side effect I know some of the codes by heart now.

    1. Never seen such a chart but i can visualize how it functions and through the side effect it’s easy(er) to read (remember) the values. Also somethimes it’s not clear from wich side to start but the first two nummers should be in a Exx (E12, E96 etc) range also a metal band (in 1e 2) means you need to start from the other side.

  15. I sort my resistors into 12 boxes. 1st has 10 Ω, 100 Ω…1 MΩ, next is 12, 120,.. 120 k etc. That way there is only one colour to check (so in the 1st box red ==> 1k, orange ==> 10k etc.) to find the correct R.

    1. Soyiu’ve remembered the sequence of colors, which I gather didn’t start with resistor color codes.

      You then have to count your way through that till you get to the color you want.

      Since I see the number when I see the color, I work faster.

  16. Anyone who can’t quickly figure out that 56 with four trailing zeros is 560K isn’t likely to be able to understand much about the circuit they’re building in the first place. This is a silly alternative.

  17. I just wish they’d leave a MUCH bigger gap between the resistance colour code and the tolerance colour ring, particularly on blue bodied through hole resistors. So easy to read them the wrong way round.

  18. The resistance is much less important than the tolerance. Its easy enough to verify resistance, but no sane way to verify tolerance. I once lost two full weeks hunting down a problem caused by a turnkey CM secretly substituting lower tolerance parts. That. Really. Sucked.

  19. the difference between these two charts is almost indiscernable to me.

    i got an assortment and spread it out over 6 drawers, one per power of 10. then each drawer has a label on it.

    xx black 0
    xx0 brown 1
    x.xk red 2
    xxk orange 3
    xx0k yellow 4
    x.xM green 5 / xxM blue 6 (in one drawer…how many 10M resistors do i need??)

    the label on the drawer is the cheat sheet, so i never lose it. i don’t have 7/8/9 written down but i know if 47 is yellow-purple so 7 is always easy to remember. if it’s white or grey, it’s an 8 or 9 and i don’t typically care which. i think there’s an actual cheat sheet that came with the assortment curled up in the last drawer too :)

  20. Sorry Andrew, but perhaps because I cut my teeth on resistor colour codes decades ago, I’ve never had a problem with the “standard” resistor colour chart. The only “resistor” issue I have is that with the ever decreasing physical size, and the tendency of chinese manufacturers to thin down the width of the colour bands , its easy to misread a band colour sometimes.

  21. I have been able to read color bands on partially burned resistors since they go all the way around. Text would have been impossible. Somehow there is something missing in this NEW cheat sheet idea. green-blue-yellow = 564 = 56 + 4 “0”s = 560000. How is that easier than 5.6 x 100K? The 3rd band is the number of 0s one adds to the value. Except if the color is not part of bbroygbvgw. Then you must think in terms of moving decimal, which works in either case. 56==56.0000000 so 564 moves the decimal 4 places to the right. Gold and silver move it in the opposite direction. My only problem with color bands is the colors are not consistent and sometimes difficult to decide if it is red or orange, orange or yellow, black or brown, gray or white, blue or green. Now, how many people remember how to read bbroygbvgw………..Hint: Bad Boys………..

    1. Some mnemonics that seem apt: Badly Burnt Resistors On Your Ground Bus Void General Warranty., Better Be Right Or Your Great Big Plan Goes Wrong – Go Start Now! And Popular in the days of vacuum-tube radios: Better Buy Resistors Or Your Grid Bias Voltages Go West

    2. Some oldies have awful paint and if they’ve run hottish but not burny, they’ve got tan, tan, tan, tolerance tan bands on now. Occasionally you can scrape oxide off carefully, and see a color, but most often it just flakes.

  22. Funny thing is, once you learn the color codes by sight, it isn’t that you are seeing a color and thinking a number or a series of numbers, you are seeing a resistor with a marking (such as brown red orange) and you instantly recognize it as a 12k resistor.
    It’s like you are seeing the color sequence as a word instead of a series of letters. Learning by chart or memorizing the name of a color (like “yellow equals four”) will never get you there. It’s a different kind of learning.

    1. Yes, this is how I see the color code. It’s similar to the way I copy Morse code. I hear a word or sequence of words as one thing, not a sequence of letters. For me this sort of thing evolves naturally over time. I suspect it’s the same for most other Humans.

  23. This proposed method makes about as much sense as common core math. Why would an entire scheme – that has worked well for over fifty years – be scrapped just because one person thinks it’s easier to start with a decimal number than it is to start with a whole number? I’m sure I am alone in this, but I think this is just change for the sake of change rather than adding any real benefit.

  24. Wait wait, does anyone realize his chart is just an elaborate way to avoid multiplying or dividing by 10 to get a scientific notation?
    So instead, he proposes having two sets of multiplier values depending on how many bands there are which is ridiculous.
    And this is because the original chart is an two or three digit number multiplied by some factor of 10. And he doesn’t like that so, divides the multiplier column by some factor to get scientific notation but now he gets in trouble. For numbers with 2 significant digits, he needs to divide by 10 but for 3 significant digits it has to be by 100. So now you have two sets of multipliers because somehow it’s more intuitive to the guy to know how many bands there has to be than by just converting to scientific notation at the end and why that was necessary to begin with is unclear.
    Apparently his brain only accepts scientific notation.

  25. You couldn’t be Color Blind back in the 80’s when I went into the US Air Force for any Telecommunications or Electronics Career Fields because the use of colors were used so much on electronic components and everything in Telecommunication cables was color coded. I was “Officially” taught to just memorize the resistor color code; but everyone pretty much relied “Un-officially” on some type of mnemonic rhyme to remember the code. I don’t think any of them were politically correct, even for the 80’s. I relied on one that starts with Bad Boys …. and ended with Willingly.

    1. We were actually taught that mnemonic in the Army electronics school in the mid-seventies, even with a few women in the class. I always felt sorry for poor old Violet. She was headed for trouble.

  26. So this guy thinks 560K is 5.6 x 100K, well what about 560 x 1K? I dont like the idea of thinking 5.6 for 560, I like the idea of 560 for 560, but what about if another whiner wants .56 x 1M??? should we do away with scientific notation? should we make new standards for everything? Look if a color code has been is used for decades, get over it. Othewise, morsecode is wrong, lets change morecode as well, I dont like … for an S, I want it a single . and a single – for O, because when I think emergency, .-. .-. is simpler and easier to understand than … — … , make the world think like me

  27. Bad contrast is my problem. I have partial color blindness that makes some brownish colors look the same, especially against that medium bluish color. Sometimes they use a bad shade like a really dark brown that almost looks black, and sometimes the stripes are really narrow too. But it helps that most of the standard values I see only use 0 1 2 and 3, except for 47, 68, and the 100K exponent. I remember the old dark brown carbon resistors from when I was a kid in the 70s, those had much better colors.

    Also, that’s a silly way to do the exponent. You just read the exponent band as the same number of zeros. Brown black orange… 1 0 3… 1 0 000… 10K ohms. it even works on 1% resistors with the extra digit, and it works with 1% resistors that have digits instead of colors.

    SMT resistors are a different problem. I had a bag of parts vacuumed from cleaning a pick-and-place machine, and I sorted the resistors into tiny bags. Sometimes it was hard to tell apart an 8 from the B used in 1% codes, and sometimes upside-down read as an equally valid value.

  28. I can’t tell what colors are what with the naked eye anyway, so I use a multimeter, but on the off chance I break out my USB microscope to read resistors I find it much easier to read the multiplier band as how many zeros to add. I read, say green blue orange, as green=5, blue=6, orange=000, for 56000 ohms, or 56k.

  29. Why not just read it as originally designed? green/blue/yellow = 5/6/4 = 5 6 and 4 zeros = 560000. Doesn’t take a lot of mental gymnastics to translate that to 560K. Just count to 3 right to left. No need to over-complicate it.

  30. The existing color code interpretation has worked so well for so long, why make a new variant now??? It will just cause more confusion for those learning. Stick with the entrenched standard. P.s. I always remember the multiplier band as the “power of ten”. Thinking of it as the “number of zeroes” also works cleanly. Unfortunately the “new” system throws the traditional read out the window.

  31. Why to complicate simple things?
    474 red violett red= 4 7 0000= 470k
    Only peoples with problem with colour recognition can have problem. But they have multimeters.

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