Tool

Logo Variant
Selector

Move the sliders, or type a HEX code, to see which variant of the logo to use on that background.

For SOT a background answers two questions, not one. The brand book allows the logo on the eight key colours “without changing its colour or any of its components” (p6, p9) — so the tool tells you which key colour to ink the mark in, and whether your background is a recommended ground at all.

Download as one file A single self-contained HTML — artwork inlined, downloads generated in the browser. Works offline, from an email attachment, with no server.
8key colours as grounds
40ink files · 5 x 8
6documented pairings · p60
3:1non-text contrast floor

Pick a ground

Guideline p6, p9, p60

Hue, saturation and brightness. Click the canvas or the filename to download the SVG.

Use this file  
Three or six hex digits.
Hue240°
0°360°
Saturation100%
0%100%
Brightness100%
0%100%
Which lockup you use is decided by the shape of the space, not by the background — see Lockups.

Every ink, ranked

Contrast is derived

All eight key colours against the current ground. Documented pairings sort first, then contrast.

Ink Hex Contrast Book Verdict
03 — Method

How it
Decides

Three checks, in order. Only the first two are brand law; the third is an engineering floor this system adds.

The three checks

CheckSourceRule
Is the ground approved? p6, p9 The logo may be placed on a recommended background colour without changing its colour or components. The recommended set is the eight key colours (p16, p44). Anything else is flagged off-palette, with the nearest key colour offered.
Is it a documented pairing? p60 The six ordered pairs of RGB Blue, RGB Green and RGB Magenta are shown in use in the brand book. These sort to the top, and are labelled, even when their contrast is low.
Does it hold up? Derived Contrast ratio against WCAG 2.2 1.4.11 non-text contrast: 3:1 minimum for a graphical object, 4.5:1 treated as strong. Not in the brand book.

Why contrast cannot be the whole answer

The brand book's own duotone pairings run from 6.26:1 down to 2.29:1. Magenta on green and green on magenta both sit at 2.29:1 — under the 3:1 floor — yet the book puts them in use on p60. They are chosen for optical vibration, not legibility.

So a plain contrast checker would mark the brand itself as wrong. This tool reports both facts instead: the pairing is documented, and its ratio is below the floor — which in practice means use it at display scale, and pick a higher-contrast ink for a small mark.