The NIX app will do the work for you. Usethe NIX Digital App to scan a pillow, for example, and the app will search as many as 42 brands to find all the paint colors that match the closest.

You can, of course, choose which brand you want to search - don't have to search all of them.

You have to tap the check in the blue circle after you select your brand. (not intuitive)

I think their tutorials are unfortunately unhelpful. But here's the link: https://www.nixsensor.com/category/tutorials/

Here's why you want to let the NIX do the work for you. HEX Codes are not the right values to use for what you want to do. HEX codes are instructions. They tell a device how much red, green and blue needs to light up to make a digital swatch of a paint color.

HEX codes don't describe what a color looks like in real life. They don't define a color's hue family, lightness or colorfulness (how clean or dirty).

Or you could use your eyes.................: ) There are many books on color flow and harmony. It's rarely "matching" that makes inviting rooms. It's complementing, and accenting that you are after.

A simple color wheel, and understanding the six types of color schemes is very helpful.

https://learn.g2.com/color-schemes

Sorry there is no better way to choose colors than the old fashioned poster board painted with 2 coats of 3 samples you like. Yes to a color wheel it helps with understanding how colors relate but all the gadgets in the world will not replace your eyes in your space not on a monitor for sure.

Colour measurement devices and colour wheels are aids to filter colour selection before finalising samples to test in a space.

Agree with what Patricia said. Painting poster board (2 coats) and putting it up in your space is the best judge of what you can live with.

The color harmony function in all the apps for devices like NIX is a digitized version of a color wheel. It's literally the same concept made portable and paperless.

A standard color wheel only shows the most chromatic hue parents and fails when it comes to illustrating color relationships between tints, tones and shades. In other words, a standard color wheel only speaks to one dimension of color, hue, and isn't formatted to help with neutrals and near neutrals.

Digitized color wheels construct color harmonies based on the basic framework of a standard color wheel BUT has the advantage because they're able to consider all 3 dimensions of color: hue, value and chroma.

This is what the NIX app looks like. It will return monochromatic color harmony results. Similar(ish) to a physical strip of chips. Which is what OP was looking for.

Only the app is better because the colors relate colorimetrically, not random like many strip chips.

Benjamin Moore's App is called Color Portfolio. It works with the ColorReader device from Datacolor.

But you don't need a ColorReader device to search their digital fandecks.

You just have to download the free app and all of the digital palette and paint functions work - again, without connecting to a ColorReader.

Benjamin Moore Color Portfolio App · More Info

You can use EasyRGB if you know the hex value. That can be matched to paint colors.

Just be aware that these inexpensive tools are designed to measure a single small dot and it may not represent a blended color (linen will often return the color of the darker, grayer thread or the lighter yellow white thread, but neither are the color you see when the two blend together and produce that gray yellow white linen color.

The site I referenced is here:

easyrgb.com

Select match color data

Choose data type (HTML)

Enter the Hex Code

Select all collections or pick a specific paint brand.

EasyRGB returns the closest matches.

It will also convert the color to different data types

It has a glitch and won't convert all data types without re-entering the information.

HTML is one that if you left click on the number and hit convert it will return ERROR as the HTML code and you have to enter the HTML code again.

But it does then convert it to all data types.

There is a whole lot of issues with pulling color data, but each tool helps some and most of us can't afford the tools that work really well and there are no tools that can read a color and tell you how the average person with normal vision will see color in context. Cannot be done.

Tools can only measure what length wavelengths are being reflected off a surface, they cannot measure how human sight interprets that data. It cannot replicate cone fatigue or the impact of dopamine or how lighting will alter your interpretation of the color or your emotional response to color. There have even been studies on rats that show that a mother rat that is surrounded by a single color during pregnancy changes the behavior of the offspring throughout their life.

Here is another website that uses hex codes and lets you explore color combinations that will appeal to you.

Our eyes tend to like geometric shapes, but there isn't some magic that says it has to be a 30 degree differential, This allows you to play with all kinds of combinations to find out what makes your heart sing.

Paletton.com

I suggest you do it both ways.

Use HEX codes and then use the NIX app.

Decide which way works best for you based on actual vs. theoretical results.