Fix: route color and text color don't contrast

Published: 3 July 2026. Last reviewed: 3 July 2026.

Code: route_color_contrast (MobilityData validator)

What this means

routes.txt lets you set route_color (the route's background colour) and route_text_color (the colour of the route name drawn on it). The two are too close in brightness, so the label is hard to read against its background.

Why it matters

Apps and maps draw the route number or name in route_text_color on a swatch of route_color. Low contrast makes that label hard to read for everyone and unreadable for low-vision riders, which undoes the point of branding the route at all. This is an accessibility fix as much as a cosmetic one.

How to fix it

• Set route_text_color to whichever of black (000000) or white (FFFFFF) contrasts more with the route colour. Dark route colours take white text; light ones take black.
• Aim for a contrast ratio of at least 4.5:1 (the WCAG AA threshold). Any online contrast checker will tell you whether a colour pair passes.
• If a route has no strong brand colour, leaving both fields blank is fine; apps fall back to readable defaults.

How long it usually takes

A few minutes: pick black or white text per route colour. A bulk edit in most scheduling tools.

Authoritative rule

route_color_contrast is a canonical MobilityData GTFS Validator notice used in validator reports across the GTFS ecosystem. Read the authoritative rule for route_color_contrast in the GTFS Validator rules. (opens on an external site)