Key:colour

From OpenStreetMap Wiki
Jump to navigation Jump to search
Public-images-osm logo.svg colour
Prague metro plan 2008.svg
Description
The colour associated with the object Show/edit corresponding data item.
Group: annotations
Used on these elements
may be used on nodesmay be used on waysmay be used on areas (and multipolygon relations)may be used on relations
Useful combination
Status: de facto

Use colour=* to indicate the official colour within the sRGB gamut associated with the object, for example the colour typically associated with a public transportation route. It is also often used to describe the real colour of an object like amenity=bench.

Important note: The key uses the English spelling of "colour" and not "color" (Americanised English spelling). Refer to deprecated tags below.

How to map

The value should be:

  • a  Web RGB colour code (hex triplet), e.g. #FF0000 for red. This RGB code allows to describe about 16 millions distinct colours.
    • A shorter RGB code with only 3 hex digits is also possible: it is equivalent to the 6-digit RGB codes where each individual digits (of the 3-digit code) are doubled (see examples in the table below). This short code (also standard in HTML and CSS) allows describing 4096 distinct colours.
  • a CSS colour name (mostly American English colour names) in lower case (generic names should be preferred for non-specific colours, e.g. red instead of firebrick), and without any dash separator (when using composite colour names in the "Extended colour set" in the CSS specification). The limitation to lower case is currently valid in spite of the CSS specification that says that colour names are ASCII case-insensitive.

Colour names

Renderers reportedly have inconsistent support for colour names. There is a dilemma when it comes to using those names:

  • The 16 "basic colour names" from CSS 1.0 are almost universally supported by renderers. They, however, are terrible in terms of legibility and aesthetics.
  • HTML has gradually evolved to use a larger list of colours (see  Wikipedia list) -- consolidated in the CSS colour Module Level 3. These colours are somewhat better, but they remain inconsistent in places (e.g. "lightpink" is darker than "pink"!). They are also not recognized by all renderers.

If you are looking to maximize all three of compatibility, legibility, and aesthetics, hexcode is the way to go.

The 16 CSS 1.0 basic colours
Sample RGB hex W3C colour name   Sample RGB hex W3C colour name
  #000000 (or #000) black   #FFFFFF (or #FFF) white
  #808080 gray (or grey)   #C0C0C0 silver
  #800000 maroon   #FF0000 (or #F00) red
  #808000 olive   #FFFF00 (or #FF0) yellow
  #008000 green   #00FF00 (or #0F0) lime
  #008080 teal   #00FFFF (or #0FF) aqua (or cyan)
  #000080 navy   #0000FF (or #00F) blue
  #800080 purple   #FF00FF (or #F0F) fuchsia (or magenta)

Taginfo

Here is a list of the most used tags on taginfo:

Value may be interpretated as RGB hex Uses Charts
colour=brown #804000 Osm element all.svg Taginfo-icon-1.svg 📈
colour=red #FF0000 Osm element all.svg Taginfo-icon-1.svg 📈
colour=yellow #FFFF00 Osm element all.svg Taginfo-icon-1.svg 📈
colour=gray #808080 Osm element all.svg Taginfo-icon-1.svg 📈
colour=green #008000 Osm element all.svg Taginfo-icon-1.svg 📈
colour=white #FFFFFF Osm element all.svg Taginfo-icon-1.svg 📈
colour=black #000000 Osm element all.svg Taginfo-icon-1.svg 📈
colour=blue #0000FF Osm element all.svg Taginfo-icon-1.svg 📈
colour=orange #FF8000 Osm element all.svg Taginfo-icon-1.svg 📈

see more on https://taginfo.openstreetmap.org/keys/colour#values

Multiple colours on an object

In case an object has several colours on it, there are the usage of namespace syntax - several colour=* prefixes (colour:*=*) and postfixes (*:colour=*) exist.

Rendering

The colour=* key is not currently rendered in any of the featured tile layers, because mapnik cannot take styling from the database.[1] Despite this, continued use and application of the key encourages the chance that it may be rendered in the future.

The tag is used in applications, such as OsmAnd / Organic Maps and some 3D visualisation programmes.

The Subway routes overlay from Tracestrack supports this tag.

Value style support
Software 3-digit hex 6-digit hex CSS basic colours CSS 3 extended colours CSS 3 "transparent" CSS 4 "rebeccapurple"
F4 Map yes yes non-standard[2] non-standard[2] no no
MapComplete yes yes yes yes no yes
OsmAnd partial[3] partial[3] non-standard partial[3] no no
OSMBuildings yes yes yes yes no yes
OSM2World no yes non-standard[2] yes no no
Streets GL no yes yes yes no yes

Deprecated tags

There was an alternative spelling color=* in use for the tag name, using the American English spelling. Conforming to the convention of using British English for tags and values this alternative was deprecated. By means of mass edits in 2021 these were migrated to colour=*. See: https://taginfo.openstreetmap.org/keys/color#chronology

Note that the names in this tag's value should still follow the W3C standard.

Possible tagging mistakes

If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!
If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!
If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!
If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!
If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!

Tools

See also

  1. https://help.openstreetmap.org/questions/12944/transport-colours
  2. 2.0 2.1 2.2 For artistic reasons, this renderer uses different RGB values for some colour names than what CSS specifies. For example, colour=yellow may render as RGB #FFEA04 instead of #FFFF00.
  3. 3.0 3.1 3.2 Converted to a set of 16 colors. #12557 (comment)