Grapheme-colour synesthesia

Another less-used name is “colour-graphemic” synesthesia

It includes letter-colour, word-colour and number-colour (digit-colour)


People with this type of synesthesia involuntarily associate certain colours with graphemes (letters, numbers and other written symbols such as punctuation marks or characters in languages with non-alphabetic writing systems). They perceive these associated colours when reading the letters, words or numbers or thinking about them.

Representations: Cyrillic (Russian): Tat Golubkova / Latin (English): Bug Catcher in Viridian Forest / Hiragana (Japanese): The9thBitYT

Representation: Pau365

It is one of the most common types of synesthesia. In fact, it can probably be considered the most common of all, as it is estimated that more than 60% of synesthetes have this type. It has also been extensively studied and is very well-known, as in addition to being common (and therefore relatively easy to find subjects of study) it is highly consistent and invariable and quite easy to verify by online testing.

How are the colours of the letters and numbers perceived?

Some synesthetes are called “projectors”, meaning they see their colours physically: if they look at a page of text, they perceive the colours to be floating in space over each letter or word or the words seem to be written in ink of that colour rather than in black. Projectors account for about 10% of synesthetes. The others are called “associators” and see their photisms in the mind’s eye. In the case of words, for example, even though they see them as being printed in black they get a very strong impression at the same time that the word is written in the colours of their synesthetic concurrent. Or it is often just a very consistent association: the synesthete “knows” that the number, letter or word is that colour but doesn’t see anything visual at all, not even in their mind’s eye.

The different ways in which projectors and associators perceive letters, numbers or words.
(from The Illustrated Synaesthetic Experience Questionnaire (ISEQ); Skelton, Ludwig, & Mohr, 2009, a questionnaire to determine whether grapheme-colour synesthetes are projectors or associators.) The first and second girls would be projectors and the rest associators.

Some people have colours for letters but not for numbers, or vice versa: not all grapheme-colour synesthetes have both types.

It’s also interesting to note that for many, not all the letters or numbers have a colour. So for example 1, 2, 3 and 5 might have a colour, but 4 doesn’t.

And there are also many cases where the symbols have more than one colour at the same time. In my own personal case, 4 is blue, but it’s also red, as nothing seems redder to me than a year ending in the number 4.

How are whole words and multi-digit numbers perceived?

When someone with this type of synesthesia reads or thinks about a word they might see each individual letter in its corresponding colour, but very few grapheme-colour synesthetes actually perceive words in this way. It appears to be much more common for the whole word to take on the colour of its initial letter, as the first letter has a more forceful presence in the word. Alternatively, the word might take on the colour of its first letter but be nuanced by the tones of one or more of the letters following it. It can also happen that one of the other letters in the word bears a particular weight for the synesthete in question, even though it is not the first letter, meaning it will “colour” the whole of the word in general. This is often the case for vowels.

"This is how I see words", by Herbie53101

For numbers, the situation is often similar: if the digit 2 is blue, for example, the compound numbers starting with 2 – 24, 250, 2000 and so on – frequently also appear as blue or some variant of it. However, for some people it is the last digit that determines the colour of compound numbers, and in other cases each number has its own unique colour even if it has two or more digits.

Is there any consensus about the colour of specific letters and numbers?

In general, no: letters and numbers can be any colour at all and it can safely be said that no two synesthetes have the exact same colours for their entire alphabet or number system. However, it is true that some colours seem to be more “popular” for certain letters and numbers. The letter ‘A’ being red is the best known case perhaps (in a study conducted in 2004, researcher Sean Day discovered that A is this colour for 44% of grapheme-colour synesthetes). White ‘I’ and black ‘Z’ also occur more frequently than dictated by chance, for example. As to numbers, ‘1’ often tends to be white and zero either transparent, colourless or with no association, although there is little consensus for the rest.

The most common colours experienced by English speaking synesthetes, as shown on Sussex University’s "Synaesthesia Research" website. 

Approximate percentages of colours for the grapheme ‘T’ (from the study Trends in synesthetically colored graphemes and phonemes by Sean Day, 2004)

Our Alphabets – an ongoing project where grapheme-colour synesthetes can add their letter colours
If you’re a grapheme-colour synesthete you might like to add your own specific colour perceptions to this ongoing chart. It’s all anonymous, and you can even add comments about your colour choices if they’re not so easy to represent. And of course anyone at all can consult it to see which choices are the most and least common for each letter. It’s an interactive Excel spreadsheet in Google Docs created by synesthete NonbinaryNor.

Emotional importance

People with this type of synesthesia tend to feel annoyed or uncomfortable when they see the symbols represented in colours different from their own. So, for example, if C is apple green for one synesthete a C written in that colour will look harmonious and “right” while a C that is blue, red or any other colour will usually give them the unpleasant sensation that it is “wrong”.

Meme of unknown authorship, 2021

How should this type of synesthesia be defined, if it’s all visual and doesn’t involve two different senses?

Despite being one of the commonest and best-known types of synesthesia, grapheme-colour is a good example of a type that does not fit in with the definition that synesthesia is “a crossing of the senses”, which was popular at one time but is now on the way to being superseded by more up-to-date definitions. Like many other types, grapheme-colour does not involve perceptions in two different senses but is a conceptual type of synesthesia, where the concept of the letters or numbers triggers a visual perception of colour. Synesthesia does not occur in response to individual, random concepts but to series or sequences of abstract concepts that are called “overlearned sequences” (sequences we learn, usually in early childhood, and then practice a lot as we have to memorise them). So grapheme-colour can in fact be classified as one of the many subtypes of coloured sequence synesthesia.

Numerosity rather than symbols as an inducer of grapheme-colour synesthesia

In the case of number-colour synesthesia, there are cases where the colour concurrent is prompted by the concept of numerosity in itself, regardless of written symbols. So, for example, some people perceive a colour when somebody holds up a certain number of fingers to show a number, or when they throw a dice and see the dots on it, or even when they look at a geometric shape or object with a certain number of sides.


This refers to spoken words, i.e. words that are heard rather than read. A grapheme is the smallest unit of written language (a letter), while a phoneme is the smallest unit of speech differentiating one word from another (a sound). Grapheme-colour for letters and phoneme-colour synesthesia are similar, but in phoneme-colour synesthesia the colour experience on seeing the letters is related to how they sound in a word rather than just their written form.

Go to the page on phoneme-colour synesthesia

Lexeme-colour and morpheme-colour

People with this variety have colour associations for the different parts of the word: the lexeme and the morpheme. The lexeme is the root of the word. It may be accompanied by one or morphemes, which are the part of the word that is joined to the lexeme to add grammatical meaning (tense, person, number, etc.):

MILLION    (lexeme)

MILLIONAIRE     (lexeme + morpheme)

MULTIMILLIONAIRE    (morpheme + lexeme + morpheme)

Go to the page on lexeme-colour and morpheme-colour

Grammatical categories-colour

For a few synesthetes, grammatical categories - parts of sentences, words or phrases that have a specific syntactic function such as conjunctions, indirect complements, adverbial phrases, etc. - are accompanied by a specific colour perception. This would be better classified as an example of coloured sequence synesthesia but not specifically grapheme-colour synesthesia. It is mentioned on the list of examples of inducers on the page on coloured sequence synesthesia.


For some synesthetes, letters, words or numbers have not only colour but also texture and other features, or they can even automatically evoke a complete image. Go to the page on grapheme-shape/colour/texture/image

Go to the page on grapheme-shape/colour/texture/image

Go to the page on phoneme-colour synesthesia

Go to the page on lexeme-colour and morpheme-colour synesthesia

Go to the page on coloured sequence synesthesia

This page is about grapheme-color synesthesia. This page is about grapheme-colour synaesthesia

This page last updated: 14 April 2024


  1. Yep zero for me is transparent and colourless. I find it frustrating and feels like trying to catch or hold water in your hands. It makes me uncomfortable when seeing zero in my head.

  2. Fake. It's just mind control screwing with the pathways in the brain. FAAAAAAAAKE