What Is a Colour Profile?
A colour profile (also called a colour space) is a set of rules that defines exactly how colour values in an image file should be rendered on a screen or in print. Without a colour profile, the same file can look very different on different devices — a red that looks vivid on one monitor might appear orange on another.
The two most common colour profiles you will encounter are sRGB (for screens and web) and CMYK (for print). Understanding when to use each prevents a very common and frustrating problem: images that look great in your design software but appear dull and washed out on a website.
What Is sRGB?
sRGB stands for Standard Red Green Blue. It was developed by HP and Microsoft in 1996 as a colour space standard for computer monitors, cameras, and the internet. It defines a specific range (gamut) of colours that virtually all consumer monitors can display.
sRGB is the colour profile for the web. Every browser assumes images are sRGB unless told otherwise. Every consumer camera saves photos in sRGB by default. Every major social media platform expects sRGB images.
What Is CMYK?
CMYK stands for Cyan, Magenta, Yellow, and Key (Black). It is the colour model used by commercial printing presses. Instead of mixing light (like RGB monitors), printing mixes ink pigments. CMYK is a subtractive colour model — adding more ink creates darker colours, unlike RGB where adding more light creates brighter colours.
CMYK is the colour profile for print. When you send a file to a commercial printer, they expect CMYK. Sending an RGB file to a professional printer results in automatic conversion, which often shifts colours in unexpected ways.
The Core Difference: Gamut (Range of Colours)
RGB monitors can display more colours than CMYK printing can reproduce. Vivid neon colours, electric blues, and bright greens that look stunning on screen may be "out of gamut" for CMYK — the printer simply cannot reproduce them with available inks and substitutes the nearest achievable colour, which is often noticeably different.
This is why designs that look vibrant on screen can look duller when printed. The solution is to design print work in CMYK from the start, so you only use colours the printer can actually reproduce.
Why CMYK Images Look Washed Out on Websites
If you upload a CMYK JPEG or PNG to a website, most browsers and image viewers will interpret the colour values as if they were sRGB — because that is what they expect. This causes colours to appear significantly desaturated and dull. The image has not changed; it is just being read through the wrong colour interpretation rules.
The fix is simple: always convert images to sRGB before uploading to the web.
How to Convert CMYK to sRGB
In Adobe Photoshop:
- Open the image
- Go to Edit → Convert to Profile
- Set Destination Space to sRGB IEC61966-2.1
- Click OK
- Save as JPEG with "Embed Color Profile" ticked
In GIMP (Free):
- Open the image
- Go to Image → Mode → RGB
- Then Image → Color Management → Convert to Color Profile
- Select sRGB as the target
- Export as JPEG
Via Command Line (ImageMagick):
convert input.jpg -profile /path/to/sRGB.icc -colorspace sRGB output.jpgWhen to Use Each Profile
| Use Case | Correct Profile |
|---|---|
| Website images | sRGB |
| Social media uploads | sRGB |
| Email images | sRGB |
| Commercial printing (brochures, business cards) | CMYK |
| Professional photography deliverables | sRGB (for screen), CMYK (for print) |
| Home inkjet printing | sRGB (home printers do their own RGB-to-CMYK conversion) |
What About Adobe RGB and ProPhoto RGB?
Adobe RGB and ProPhoto RGB are wider colour spaces that capture more colours than sRGB. Professional photographers sometimes shoot in Adobe RGB to preserve a wider gamut for print workflows. However, these wider profiles cause the same "washed out" problem on the web as CMYK — browsers do not understand them. Always convert to sRGB before publishing any image online.
Should You Embed Colour Profiles in Images?
Yes, always embed the sRGB colour profile in images exported for the web. This adds a tiny amount of data (a few hundred bytes) but ensures that colour-managed applications render your image correctly. In Photoshop, tick "Embed Color Profile" when saving. In GIMP, use "Export with color profile".
Summary
Use sRGB for anything going online — websites, social media, email. Use CMYK for commercial print files — brochures, business cards, posters. If your image looks dull on a website, convert it from CMYK to sRGB in Photoshop (Edit → Convert to Profile) and re-upload. Always embed the sRGB profile when exporting for the web to ensure consistent colour rendering across all browsers and devices.