Cook's Blue vs RAL 650-3
Where Cook's Blue belongs to Farrow & Ball's range, RAL 650-3 is a RAL Effect color. These are both blues, so the question isn't which hue to choose — it's where within blue to land. Cook's Blue (LRV 25) reflects noticeably more light than RAL 650-3 (LRV 8), a difference of 17 points that becomes especially apparent in rooms with limited natural light. With a ΔE of 18.4, the contrast is hard to miss. These aren't variations on a theme — they're two different answers to the same question. Below you'll find 3 real-room photo comparisons where both colors appear side by side, plus 5 simulated room previews.
Cook's Blue vs RAL 650-3 in Real Spaces
3 real rooms side by side. Seeing Cook's Blue and RAL 650-3 in actual rooms makes the difference concrete; browse the spaces below to get a feel for how each color lives on a wall.
Living Room
In a living room, color works across both daylight and evening light — the same wall can read very differently at noon and at 8pm. The LRV gap is large enough that Cook's Blue will make the room feel meaningfully brighter than RAL 650-3 would.
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. Cook's Blue reflects noticeably more light off the walls, making the space read more open than RAL 650-3.
Kitchen Cabinets
Kitchen cabinets are constantly compared against adjacent materials, which means subtle differences between these two become much more visible. Cook's Blue reflects noticeably more light off the walls, making the space read more open than RAL 650-3.
Color Details
Cook's Blue vs RAL 650-3 Simulated Comparison
5 simulated room previews — drag the slider on each to see Cook's Blue on one side and RAL 650-3 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 Cook's Blue comparisons
See how Cook's Blue stacks up against other well-photographed colors across different brands and tones.
