Valley of Tears

#d1e1e4

A neutral that has no useful hue — it reads as a grey. It is very light — it works as a page background, not as text.

Hex

#d1e1e4

RGB

209, 225, 228

OKLCh

89.9% 0.018 210.2°

CIELAB (D50)

88.4, -5.1, -3.4

What is true of this colour, and of no other

43 other named colours sit within ΔE00 2 of it — this part of the space is crowded, and the names here are finer distinctions than most people make.
It uses only 19% of the chroma available at this lightness and hue — there is a far more vivid version of this colour inside sRGB.
As text on white it measures APCA Lc 17.0; on black, Lc -86.6. The sign is the polarity, which the WCAG ratio discards.
Built into an eleven-step scale, 10 of the 10 adjacent pairs stay ΔE00 2 apart — see the ramp.
protanopia and deuteranopia and tritanopia shift it by ΔE00 7.4 and 8.0 and 15.3 — no red cone.

Text on this colour

White text

1.35:1 — fails AA

Black text

15.60:1 — passes AA

Black text is the better of the two at15.60:1. That is enough for body text.

As text on white, it needs to change

#6b797c is the nearest colour of the same hue that passes AA on white, at 4.50:1. Only the lightness moved.

Try it against your own background

The same colour, with one cone missing

As you see it

#d1e1e4

protanopia

#dfdfe4 · ΔE00 7.4

deuteranopia

#dcdce4 · ΔE00 8.0

tritanopia

#d9d9ff · ΔE00 15.3

Run a whole palette through all three

The twelve nearest named colours

Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isCool Sky at ΔE00 0.59: below 1.0 — an ordinary observer cannot tell these apart, even side by side. What the numbers mean.

Cool SkyΔE00 0.59 · #cfe0e4
Bubbles in the AirΔE00 0.641 · #d3e3e5
Ski WhiteΔE00 0.764 · #d2e3e5
Spa RetreatΔE00 0.809 · #d4e4e6
High SierraΔE00 0.815 · #cedee2
NymphaeaceaeΔE00 0.818 · #cee0e3
Aqua SparkleΔE00 0.896 · #d3e4e6
Lauren’s SurpriseΔE00 0.998 · #d5e5e7
AloofΔE00 1.058 · #d4e2e6
WaterfrontΔE00 1.143 · #d4e4e5
Liquid HydrogenΔE00 1.21 · #cedfe0
April WindsΔE00 1.238 · #d5e2e5

11 of these have no page of their own: pages exist for the 4,961 colours the dataset marks as good names.