text_min_contrast_ratio = nil

Since: Nightly Builds Only

The functionality described in this section requires a nightly build of wezterm. You can obtain a nightly build by following the instructions from the Download section.

An optional floating point value that defaults to nil (not being set).

When set, it defines the minimum contrast ratio between the foreground and background color of a textual cell, when the cell has differing foreground and background colors.

If the color attributes of a cell fall below the minimum contrast ratio, then the foreground color will have its luminance (perceived brightness) adjusted to try to boost the contrast ratio to meet the specified minimum.

This may cause the foreground color to either increase or decrease in luminance, typically making it either more white or more black.

It may not be possible to achieve the requested minimum ratio, in which case a slightly better or the original color (if no better color can be computed) will be used.

If the foreground and background colors in a cell are identical, then that is assumed to be deliberate and the colors will remain unchanged by this setting.

WCAG 2.0 level AA requires a contrast ratio of at least 4.5:1 for normal text, so setting text_min_contrast_ratio = 4.5 is a reasonable value if you find that your selected color scheme has poor contrast in the applications that you run in your terminal.

In the screeshot below, the upper portion shows the default wezterm color scheme, while the lower portion shows how it renders with text_min_contrast_ratio = 4.5.