Route color and text color do not contrast

Published: 3 July 2026. Last reviewed: 22 October 2026.

Code: route_color_contrast (MobilityData validator)

The short answer

route_color and route_text_color are too close in brightness to read. Fix: set route_text_color to 000000 or FFFFFF, whichever contrasts more.

What this means

routes.txt lets you set route_color (the route's background color) and route_text_color (the color 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 color. Dark route colors 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 color pair passes.
• If a route has no strong brand color, 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 color. 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)