Signal blue vs RAL 640-5
Where Signal blue belongs to RAL Classic's range, RAL 640-5 is a RAL Effect color. Both sit in the blue family, which is useful context if you're narrowing within a single hue direction. Signal blue (LRV 10) reflects noticeably more light than RAL 640-5 (LRV 6), a difference of 4 points that becomes especially apparent in rooms with limited natural light. At ΔE 1.3, these are close — the kind of difference that matters when choosing between them, but doesn't read strongly in a finished room. Below you'll find 1 real-room photo comparison where both colors appear side by side, plus 5 simulated room previews.
Signal blue vs RAL 640-5 in Real Spaces
1 real room side by side. Signal blue and RAL 640-5 are close enough that the difference can be hard to judge from a chip alone — these photos show how each reads at scale, across different spaces and lighting conditions.
House
Seen across an entire facade, subtle tonal differences become pronounced. What reads as nearly the same on a chip often reads as clearly different at scale. Signal blue reads slightly lighter here — a subtle but real difference in how open the space feels.
Color Details
Signal blue vs RAL 640-5 Simulated Comparison
5 simulated room previews — drag the slider on each to see Signal blue on one side and RAL 640-5 on the other.
Digital color is approximate. These simulations are generated from the manufacturer's hex values and overlaid on grayscale room photos — your screen's calibration, brightness, and viewing angle all affect how they render. Before committing to either color, test physical samples in your own space under the light you actually live with.
More Signal blue comparisons
See how Signal blue stacks up against other well-photographed colors across different brands and tones.
