# Ink colors on packaging
**URL:** https://boards.straightdope.com/t/ink-colors-on-packaging/943545
**Category:** Factual Questions
**Created:** [June 3, 2021, 3:26pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545 "2021-06-03T15:26:50Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@MikeF](https://boards.straightdope.com/u/MikeF)
#### Post date: [June 3, 2021, 3:26pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/1 "2021-06-03T15:26:50Z")
I’m eating a bag of Planters peanuts and count 22 dots of color on the back of the bag. I’ve seen similar on other packaging and assume that these are samples of the colors used on the packaging. What is the purpose of displaying the colors?
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### Author:  [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)
#### Post date: [June 3, 2021, 3:32pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/2 "2021-06-03T15:32:56Z")
I’ve seen such things and I think they’re used for [color registration](https://en.wikipedia.org/wiki/Printing_registration); three or four ink colors are used and the dots (or the colored lines I’ve seen on boxes) are used to align the colors to ensure the image looks correct.
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### Author:  [@beowulff](https://boards.straightdope.com/u/beowulff)
#### Post date: [June 3, 2021, 3:33pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/3 "2021-06-03T15:33:11Z")
They are usually put there to check the registration of the various inks.
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### Author:  [@MikeF](https://boards.straightdope.com/u/MikeF)
#### Post date: [June 3, 2021, 4:13pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/4 "2021-06-03T16:13:07Z")
Ignorance fought. Well done.
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### Author:  [@Tabco](https://boards.straightdope.com/u/Tabco)
#### Post date: [June 3, 2021, 4:56pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/5 "2021-06-03T16:56:18Z")
They can also be used to ensure the colors are “correct.” You can use a device called a densitomer to divine the color and ensure it matches the prepress proof. In other words, that it matches the sample your customer has OK’d.
If you ever get your hands on a commercially printed item that hasn’t been trimmed, you’ll often find these dots on the margin. During trimming and cutting they get removed.
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### Author:  [@DesertDog](https://boards.straightdope.com/u/DesertDog)
#### Post date: [June 3, 2021, 7:02pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/6 "2021-06-03T19:02:00Z")
Even magazines do it. I got a copy of _National Geographic_that was badly folded before it was trimmed and a few of the pages had both registration marks – circles with CMYK in each quarter – and smaller test dots that I presumed checked the cyan, for example, was not running low.
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### Author:  [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)
#### Post date: [June 3, 2021, 7:05pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/7 "2021-06-03T19:05:03Z")
I break all of the glued folds on paperboard boxes so I can flatten them for recycling, and usually under one of the glued folds, I can find the registration marks.
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### Author:  [@needscoffee](https://boards.straightdope.com/u/needscoffee)
#### Post date: [June 3, 2021, 7:10pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/8 "2021-06-03T19:10:33Z")
> [@Tabco](#):
>
> You can use a device called a densitomer
Nitpick: densitometer
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### Author:  [@Tabco](https://boards.straightdope.com/u/Tabco)
#### Post date: [June 3, 2021, 7:14pm UTC](https://boards.straightdope.com/t/ink-colors-on-packaging/943545/9 "2021-06-03T19:14:53Z")
Yeah, that’s definitely the word I had in my head. Not sure how I missed that misspelling.