How To Select The Best Sign Colours

Choosing the best colours to make your signage stand out can be difficult. We’ve put together some tips on the best colour combinations for printed indoor and outdoor signs.

When it comes to legibility of a sign, there are many factors to consider; the environment, light conditions, distance from the reader, but one factor you can control is the contrast between the foreground and the background colour of the sign.

It is pretty obvious to most people when colour combinations totally clash, but there is also a formula you can apply using something called the light reflectance value (LRV). You can use a calculator to find out the LRV of various colours, which then can be used in your formula. Once you have noted the LRV of the colours you’d like to use, you can then find out the contrast using the following formula:

Contrast = ( B1 – B2 ) x 100 / B1
B1 = light reflectance value (LRV) of lighter colour
B2 = light reflectance value (LRV) of darker colour

Admittedly, this might be overkill for a single sign, but for events and exhibitions it is an invaluable tool for taking the guesswork out of sign optimisation.

We have put together a few contrast scores for common colour combinations, to give you an idea of what works and what doesn’t, along with some common meanings and usages.

Black Background

  1. White on black: 91/100
  2. Yellow on black: 89 /100


Meaning: power, morose, formality and mystery

Usage: airports, office buildings, information signs

White Background

  1. Black on white: 91/100
  2. Red on white: 84 / 100
  3. Blue on white: 82 / 100


Meaning: goodness, innocence, purity, virginity, perfection. positiveness

Usage: museum signage, office buildings, retail signage, school signs

Red Background

  1. White on red: 84/100
  2. Yellow on red: 82 / 100
  3. Black on red: 39/100


Meaning: war, danger, strength, power, determination, passion, love

Usage: warning signs. Attention grabbing banner, retail sale graphic

Yellow Background


  1. Black on yellow: 89 / 100
  2. Red on yellow: 82 /100
  3. Blue on yellow: 79 / 100

Meaning: joy, happiness, intellect, and energy.

Usage: airports, office buildings, information signs.

Blue Background


  1. White on blue: 82/100
  2. Yellow on blue: 79 / 100

Meaning: depth, stability, wisdom, trust, loyalty

Usage: road signs, public transport, public spaces

Check out our Pinterest colour board for more useful tips on colour schemes and combinations.