True Blue
#010fcc
A blue that is about as vivid as sRGB can show at this lightness. It is dark — it carries white text and needs care with black.
Hex
#010fcc
RGB
1, 15, 204
OKLCh
38.9% 0.260 264.3°
CIELAB (D50)
23.7, 54.3, -92.7
What is true of this colour, and of no other
- 7 other named colours sit within ΔE00 2 of it.
- It uses 97% of the chroma sRGB can show at this lightness and hue — close enough to the boundary that a wider display would show it slightly more vividly.
- As text on white it measures APCA Lc 92.3; on black, Lc -10.1. 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.
- All three dichromacies see it as very nearly the same colour you do: its hue is not the part carrying its identity.
Text on this colour
White text
10.82:1 — passes AA
Black text
1.94:1 — fails AA
White text is the better of the two at10.82:1. That is enough for body text.
The same colour, with one cone missing
As you see it
#010fcc
protanopia
#0e0ecc · ΔE00 0.4
deuteranopia
#0b0bcc · ΔE00 0.5
tritanopia
#0808ce · ΔE00 0.6
The twelve nearest named colours
Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isVesper at ΔE00 0.231: below 1.0 — an ordinary observer cannot tell these apart, even side by side. What the numbers mean.
- VesperΔE00 0.231 · #0011cc
- Medium BlueΔE00 1.294 · #0000cd
- Lady of the SeaΔE00 1.342 · #0000cc
- Evil EyeΔE00 1.425 · #1100cc
- BluealiciousΔE00 1.885 · #0000dd
- Too Dark TonightΔE00 1.979 · #0011bb
- UltramarineΔE00 1.998 · #1805db
- Nightfall in SuburbiaΔE00 2.088 · #0011dd
- Pure BlueΔE00 2.389 · #0203e2
- TetraammineΔE00 2.436 · #1e20c7
- Keese BlueΔE00 2.799 · #0000bc
- Antarctic CircleΔE00 2.91 · #0000bb
10 of these have no page of their own: pages exist for the 4,961 colours the dataset marks as good names.