Convert CMYK to RGB Cyan Magenta Yellow Black ↔ Red Green Blue Free Online Secure
Type a value in CMYK and read it in RGB at once. The arithmetic happens in your browser, nothing is sent anywhere, and what the conversion depends on is written out below rather than assumed.
Nothing uploaded
Where these notations come from
Hex and RGB are the same thing written twice. A screen colour is three numbers — how much red, green and blue light to emit — each from 0 to 255, which is one byte; hex simply writes those bytes in base sixteen, so #FF8800 and rgb(255, 136, 0) are the same instruction to the same pixel. HSL was invented because neither is readable by a human: it gives hue as an angle around a colour wheel, with saturation and lightness as percentages, so a designer can make something lighter without recomputing three figures. CMYK belongs to a different world altogether — ink rather than light. It is subtractive, built from four printing plates, and it cannot reach every colour a screen can, because a screen emits light while paper only reflects it.
Where you meet them
Hex is what you type into a stylesheet and what a design tool hands you. RGB appears wherever a colour needs arithmetic — gradients, transparency, code that computes a shade. HSL is what you reach for when adjusting a palette by hand, because the changes you want are usually changes of one of its three numbers. CMYK is what a printer asks for, and converting into it is the moment a design stops being light and becomes ink.
Questions people ask
Why does my CMYK result differ from what my printer gives me?
Because there is no single correct conversion. The arithmetic on this page is the simple, device-independent one, which is the right answer when you need a starting point or a rough equivalent. A print shop converts through a colour profile that accounts for the specific ink, paper and press, and the same RGB colour will produce different CMYK values on glossy stock than on uncoated. For anything that must match, ask the printer for their profile rather than trusting a formula.
Why can't some screen colours be printed?
Because the two cannot reach the same colours. A screen makes colour by adding light and can produce a vivid, saturated cyan or green that ink simply cannot match; paper makes colour by absorbing light, and the brightest it can ever be is the white of the page. The set of colours each can reach is called its gamut, and where they do not overlap, a conversion has to choose the nearest available colour. That is why a bright screen colour often looks slightly dulled in print.
Is the answer exact?
Where both units are defined in terms of one another by whole numbers, yes — the page says so above the figure, and the only rounding is in how many digits are shown. Where the ratio has no finite decimal, the page shows twelve significant digits and says the relation is approximate rather than pretending otherwise.
Does anything I type leave my device?
No. The arithmetic runs in your browser; nothing is uploaded and there is no server to upload it to. Load the page once and it keeps working with the network switched off.
Why you convert CMYK to RGB
The colours of print are written as four percentages: cyan, magenta, yellow and black. A brand guide gives a green as 75, 0, 25, 52. A printer's job sheet says the cover is 0, 22, 44, 65. A leaflet from last year uses a blue that nobody wrote down on screen. Now you have to use these colours on a website, in a presentation or in a social media post, where only red, green and blue exist. To convert CMYK to RGB is to take the colour that was made for ink and find the screen colour that stands closest to it.
It is worth being clear about what the conversion can offer. A printed colour is the result of ink, paper and light, and a screen colour is the result of light alone. Converting faithfully between them needs the profile of the press, of the paper and of your monitor. Without those, you get the standard formula every web tool uses, which is good enough to pick a colour on screen and a fair starting point for matching print, but not an exact match. This page does not claim more than that. It does the arithmetic in your browser, shows its working and tells you where the honest limits are.
Nothing is uploaded. Below you will find the formula, a worked example, what the conversion keeps and what it cannot, why colours from the formula often look brighter than the printed original, the situations in which people need to convert CMYK to RGB, and a few habits that keep print and screen versions of a brand in step.
How the conversion works
From ink to light
The formula treats each ink as a filter that removes some of the light. Cyan removes red, magenta removes green and yellow removes blue; black removes a share of everything. So the red you see is what is left after cyan and black have taken their share, and likewise for green and blue. In numbers, each channel is 255 multiplied by one minus the matching ink, multiplied by one minus the black: R = 255 × (1 − C) × (1 − K), G = 255 × (1 − M) × (1 − K), B = 255 × (1 − Y) × (1 − K).
The example
For cmyk(0%, 22%, 44%, 65%), the factor for black is 1 − 0.65 = 0.35. Red is 255 × 1 × 0.35 = 89. Green is 255 × 0.78 × 0.35 = 70. Blue is 255 × 0.56 × 0.35 = 50. The result is rgb(89, 70, 50), which is the colour the page starts with, and in hex #594632.
Percentages as input
The four numbers are percentages from 0 to 100. The page accepts them with or without the percent sign. A value outside the range is limited to it, since neither negative ink nor more than a full plate is meaningful.
What the conversion keeps and what it cannot
It keeps the colour as close as a formula can
The result is the colour as close as a formula can put it, and the four plates in the order a printer expects them: cyan, magenta, yellow and the black that carries the shadows. The black is applied to all three channels, which is how it works on paper, where a layer of black ink darkens everything beneath it.
The honest limit: there is no single correct answer
Ink on paper and light on a screen are different things, and converting faithfully between them needs the profile of the press, of the paper and of your monitor. Without those, what you get is the standard formula every web tool uses: good enough to pick a colour on screen, not good enough to say that the web version and the printed version are the same. Treat the numbers as a starting point and compare against a printed sample.
Two more things the formula cannot carry
A rich black mixed from several inks comes through as a flat dark colour, with no trace of the inks that made it. And a spot colour has no CMYK equivalent at all, so if the original was a Pantone ink, any four-colour breakdown is already an approximation, and the screen colour from it is an approximation of an approximation.
Whole percents
Because the four numbers are written as whole percents, a colour taken across and back can land one step away: #5A4632 returns as #594632. The difference is invisible. It does mean that the round trip is not exact, so keep the original values as the master.
Why the formula's colours look brighter
The formula ignores the paper
Paper is never perfectly white, and ink never perfectly absorbs. A printed page reflects only part of the light that falls on it, which makes every printed colour a little darker and duller than its formula value. When you convert CMYK to RGB and put the result on a screen, which shines, the colour appears brighter and cleaner than the print. That is the formula being simple, not the printer being wrong.
Pure inks are not the colours of the formula
The formula assumes that 100% cyan is exactly rgb(0, 255, 255), a pure cyan. A real cyan ink is deeper and less green, and its screen equivalent is closer to rgb(0, 174, 239) in common profiles. So solid inks look far brighter in the formula than they are in real life. Colours with a high ink value are the ones where the gap is largest.
Profiles close the gap
A colour-managed workflow uses an ICC profile of the press to translate CMYK to a device-independent colour, and then the profile of your screen to display it. In a layout program with the right profile, a soft proof on screen comes close to the print. The formula on this page is the simple version of that process, without any profile.
Where you meet the conversion
Putting a print brand on the web
A company whose brand was defined for print has CMYK values and no screen values. To build a website that matches, a designer converts CMYK to RGB, compares the result with a printed sample under daylight, and adjusts until the two look alike. The final screen values are then recorded in the brand sheet.
Reading a printer's specification
A job sheet lists cover colours in CMYK. To get a feel for what they are, before the proof arrives, you can convert them to RGB and see them on screen. It is not the print, but it is a preview of the hue and the depth.
Mock-ups and presentations
When you show a client how a printed leaflet will look in a presentation, the colours must be screen colours. Converting the leaflet's CMYK values is the first step, followed by a visual check.
Digitising old material
A scan of a printed piece gives screen colours, but a specification gives only CMYK. If you want to recreate a design from the specification, converting its colours gives you a base to work from.
How to convert CMYK to RGB here
Type the four percentages
Enter the colour in the first field in the form cmyk(0%, 22%, 44%, 65%), or just the four numbers separated by commas or spaces.
Read the rgb value
The answer appears at once, as in cmyk(0%, 22%, 44%, 65%) = rgb(89, 70, 50). The three numbers run from 0 to 255.
Compare with the print
If you have a printed sample, hold it next to the screen in daylight. Adjust the rgb values by eye if you need a closer match, and record the values you end up with.
Where these notations come from
Hex and RGB are the same thing written twice
A screen colour is three numbers, how much red, green and blue light to emit, each from 0 to 255, which is one byte. Hex simply writes those bytes in base sixteen. If you want the hex code of a CMYK colour directly, CMYK to HEX does both steps at once.
HSL and CMYK
HSL was invented because neither is readable by a human: it gives hue as an angle around a colour wheel, with saturation and lightness as percentages, so a designer can make something lighter without recomputing three figures. CMYK belongs to a different world altogether, ink rather than light. It is subtractive, built from four printing plates, and it cannot reach every colour a screen can, because a screen emits light while paper only reflects it.
Traps when you convert CMYK to RGB
Expecting a match with the print
The screen colour will be close in hue and different in depth. Compare under daylight against a real sample and adjust.
Treating 100% black as pure black
With K at 100% the formula gives rgb(0, 0, 0), but printed black is a dark grey that reflects a little light. Many designers prefer rgb(20, 20, 20) or similar for text that must look like printed black.
Converting again and again
Each conversion between the two systems adds error. Convert once, from the original CMYK, and keep the result.
Forgetting that a spot colour is not CMYK
If the brand colour is a Pantone ink, ask for its official screen values, which the ink maker publishes, and use those instead of a formula.
Questions people ask before converting
What is cmyk(0%, 0%, 0%, 0%) in RGB?
rgb(255, 255, 255), white: no ink on white paper.
What is cmyk(0%, 0%, 0%, 100%) in RGB?
rgb(0, 0, 0), black by the formula, although printed black looks less deep.
Why does my printed colour look duller?
Because paper reflects only part of the light and inks are not perfect filters. The formula knows nothing of either.
Is the conversion exact?
It is exact arithmetic on a simplified model. The result is a good starting point, not a match for the print.
Is my colour uploaded?
No. The arithmetic runs in your browser and nothing is sent anywhere.
How do I go back?
With RGB to CMYK.
Habits that keep print and screen in step
Keep a brand sheet with both
Write each colour in both forms, with a note on how the match was made: by profile, by eye against a sample, or by formula. The next person who needs to convert CMYK to RGB then knows how far to trust the numbers.
Record the sample you matched against
Keep a printed swatch in a drawer, with the date and the press. It is the only truth that matters when two people disagree about a colour.
Use profiles in design software
Layout and image programs can convert with ICC profiles and show soft proofs. Set them up once, and your screen will come much closer to the print than any web formula.
Do not edit converted colours endlessly
Once the screen version has been matched, record it and stop. Further tweaking on different screens only leads to versions that nobody can reproduce.
Making the screen version trustworthy
Match by eye in controlled light
After you convert CMYK to RGB, the best check is the old-fashioned one. Hold a printed sample beside the screen, in daylight and not under a coloured lamp, with the screen brightness at a normal level. Look at the two for a few seconds, and then look away and back. If the screen looks clearly brighter or bluer, reduce its saturation a little. It is not scientific, but it is how most brand colours have been matched for years.
Calibrate if colour matters
An uncalibrated monitor can be off by a noticeable amount in colour and brightness. If your work depends on matching print and screen, a hardware calibrator is a small investment. Without it, your match may look right on your own screen and wrong everywhere else.
Use the sample as the authority
When people disagree about a colour, point at the printed swatch, not at the screen. Screens differ, and the swatch is the reference that the brand guide describes. Whenever you convert CMYK to RGB, think of the result as a description of the swatch for use on screens, and not as the colour itself.
Be consistent across the web
Once you have settled on a screen value, use it everywhere on the site, in the emails and in the presentations. A brand that shows three slightly different greens on three pages looks careless even if each green is defensible.
Related converters
The same family of tools covers the neighbouring conversions. To go back, use RGB to CMYK. For hex codes, there are CMYK to HEX and HEX to CMYK, and for the screen notations themselves, RGB to HEX, HEX to RGB and HEX to HSL. For documents ready for print, compress PDF makes a file lighter for sending.
A worked example
Say a company's brochure from three years ago uses a green specified as cmyk(75%, 0%, 25%, 52%), and the new website must match it. You type the four numbers and read rgb(31, 122, 92), which is #1F7A5C. You build the page with that colour, then hold the brochure next to the screen in daylight. The brochure looks a little deeper, so you lower the lightness slightly, to #1B7155, and agree on it with the designer. The brand sheet now lists the CMYK, the formula's RGB and the matched RGB, each marked as such.
A short checklist
Before converting
Find out whether the colour is process CMYK or a spot ink, and whether you have a printed sample.
While converting
Type the four percentages, read the rgb value and note it as a starting point.
After converting
Compare against a print in daylight, adjust by eye if needed and record the final values with a note of how they were obtained.
Common mistakes
Trusting the formula as a match
It is a starting point. The print decides.
Using 100% black as the colour of text
Printed black is softer than pure black on screen. Choose a very dark grey if you want the same impression.
Converting in circles
Go once from the original and keep the result.
Your colours stay on your device
The calculation happens locally. Your values are used by your own browser and nothing is sent anywhere. There is nothing to delete afterwards and no account to create. That is the plain way to convert CMYK to RGB.
Summary
To convert CMYK to RGB here, type the four percentages and read the rgb value at once, using R = 255 × (1 − C) × (1 − K) and the same for green and blue. The result is the colour as close as a formula can put it. There is no single correct answer, because ink on paper and light on a screen are different things, and converting faithfully needs the profile of the press, of the paper and of your monitor. A rich black comes through as a flat dark colour, a spot colour has no CMYK equivalent, and whole percents mean a round trip can land a step away. Treat the numbers as a starting point and compare against a printed sample. Nothing is uploaded.