What does Hex Luminance do that other Design pages on this site do not?

WCAG relative luminance; tip says light or dark. Short version: Relative luminance with light/dark tip.

Does Hex Luminance upload my file or text to Tool-You servers?

No. Hex Luminance runs in this browser tab. Files stay on the device. Limit note: Needs a valid hex color.

Should I use Contrast Checker instead of Hex Luminance?

Use Hex Luminance when you need Relative luminance with light/dark tip. Use Contrast Checker when you need WCAG contrast ratio for two colors. They share a category (Design) but not the same job.

What are the limits of Hex Luminance?

Needs a valid hex color. Also: WCAG relative luminance; tip says light or dark.

Hex Luminance

Relative luminance with light/dark tip.

WCAG relative luminance; tip says light or dark.

What Hex Luminance does

WCAG relative luminance; tip says light or dark.

Hex Luminance sits in the Design group on purpose. It is not Contrast Checker (WCAG contrast ratio for two colors.) and not Color Picker (Hex, RGB, and HSL from a color.). Choose this page when you need Relative luminance with light/dark tip. If you stretch Hex Luminance into a neighbor’s job, the result will look wrong even though the site chrome looks the same.

How to use Hex Luminance

Use Hex Luminance for this design job (design · hex luminance). Contrast Checker is adjacent (WCAG contrast ratio for two colors.) but not the same.
Add the file type Hex Luminance accepts. Hint from the path: design · hex luminance. Relative luminance with light/dark tip.
Set only the options that match Hex Luminance. Neighbor Color Picker does something else (Hex, RGB, and HSL from a color.). Tool note: WCAG relative luminance; tip says light or dark.
Run Hex Luminance in this tab. Browser memory still applies: Needs a valid hex color.
Download or copy the result from Hex Luminance. If it is the wrong job, open Contrast Checker instead.

When not to use Hex Luminance

Skip Hex Luminance when a neighbor tool matches better — start with Contrast Checker or Color Picker — or when the description already warns the job will fail. In the tool’s own words: WCAG relative luminance; tip says light or dark.

Questions about Hex Luminance

What does Hex Luminance do that other Design pages on this site do not?: WCAG relative luminance; tip says light or dark. Short version: Relative luminance with light/dark tip.
Does Hex Luminance upload my file or text to Tool-You servers?: No. Hex Luminance runs in this browser tab. Files stay on the device. Limit note: Needs a valid hex color.
Should I use Contrast Checker instead of Hex Luminance?: Use Hex Luminance when you need Relative luminance with light/dark tip. Use Contrast Checker when you need WCAG contrast ratio for two colors. They share a category (Design) but not the same job.
What are the limits of Hex Luminance?: Needs a valid hex color. Also: WCAG relative luminance; tip says light or dark.