Charcoal Slate vs Sapphire blue

Charcoal SlateBenjamin MoorevsSapphire blueRAL ClassicΔE 27.9Very different colors

Where Charcoal Slate belongs to Benjamin Moore's range, Sapphire blue is a RAL Classic color. Hue-wise, Charcoal Slate belongs to the grey family and Sapphire blue to the blue family. Charcoal Slate (LRV 15) reflects noticeably more light than Sapphire blue (LRV 6), a difference of 8 points that becomes especially apparent in rooms with limited natural light. With a ΔE of 27.9, 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 6 real-room photo comparisons where both colors appear side by side, plus 5 simulated room previews.

Charcoal Slate vs Sapphire blue in Real Spaces

6 real rooms side by side. Seeing Charcoal Slate and Sapphire blue 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 Charcoal Slate will make the room feel meaningfully brighter than Sapphire blue would.

Charcoal SlateBenjamin Moore HC-178 living room fireplace

@mlevac_design

Sapphire blueRAL Classic Sapphire blue 5003 stairs

@jak_chemia

Bedroom

The context that matters most in a bedroom is how a color reads under a bedside lamp at night, not under noon daylight. Charcoal Slate reflects noticeably more light off the walls, making the space read more open than Sapphire blue.

Charcoal SlateBenjamin Moore Charcoal Slate bedroom color review

@nickysinteriorpainting

Sapphire blueRAL Classic 5003 bedroom accent wall

@sentimouk

Bathroom

Bathrooms are one of the few spaces where you're genuinely enclosed by the paint color, which makes the choice between these two more consequential. Charcoal Slate reflects noticeably more light off the walls, making the space read more open than Sapphire blue.

Charcoal SlateBenjamin Moore HC-178 bathroom wall panelling

@little_blueberry_homestead

Sapphire blueRAL Classic 5003 bathroom vanity

@miedzy_modern_a_farmhouse

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. Charcoal Slate reflects noticeably more light off the walls, making the space read more open than Sapphire blue.

Charcoal SlateBenjamin Moore HC-178 house exterior review

@tjspaintingcompany

Sapphire blueRAL Classic Sapphire blue house exterior color

@menuiserie.pierrevincent

Front Door

A front door is a focal point — small color differences read clearly at this concentrated scale. The LRV gap is large enough that Charcoal Slate will make the room feel meaningfully brighter than Sapphire blue would.

Charcoal SlateBm Charcoal Slate Front Door

@insta.gramma_

Sapphire blueRAL Classic Sapphire blue front door paint

@schildersbedrijf_hanstreffers

Kitchen Cabinets

Kitchen cabinets are constantly compared against adjacent materials, which means subtle differences between these two become much more visible. Charcoal Slate reflects noticeably more light off the walls, making the space read more open than Sapphire blue.

Charcoal SlateCharcoal Slate kitchen cabinets

@designit.buildit

Sapphire blueRAL Classic 5003 kitchen cabinets inspiration

@theladypaintdecor

Color Details

Charcoal Slate
Benjamin Moore · HC-178
Hex#646769
LRV14.5
BrandBenjamin Moore
NumberHC-178
UndertoneBlue
TemperatureNeutral
BrightnessDark
Sapphire blue
RAL Classic · RAL 5003
Hex#1F3855
LRV6.2
BrandRAL Classic
NumberRAL 5003
Undertone
Temperature
BrightnessDark

Charcoal Slate vs Sapphire blue Simulated Comparison

5 simulated room previews — drag the slider on each to see Charcoal Slate on one side and Sapphire blue on the other.

Bathroom
Bedroom
House
Kitchen Cabinets
Living Room

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 Charcoal Slate comparisons

See how Charcoal Slate stacks up against other well-photographed colors across different brands and tones.

White Dove
Charcoal Slate
White Dove
Benjamin Moore
White Dove
LRV 83

White Dove is the lighter choice

Ammonite
Charcoal Slate
Ammonite
Farrow & Ball
Ammonite
LRV 69

Ammonite is the lighter choice

Iron Ore
Charcoal Slate
Iron Ore
Sherwin-Williams
Iron Ore
LRV 6

Charcoal Slate reads slightly lighter

Purbeck Stone
Charcoal Slate
Purbeck Stone
Farrow & Ball
Purbeck Stone
LRV 52

Purbeck Stone is the lighter choice

Evergreen Fog
Charcoal Slate
Evergreen Fog
Sherwin-Williams
Evergreen Fog
LRV 30

Evergreen Fog reads noticeably lighter

Mizzle
Charcoal Slate
Mizzle
Farrow & Ball
Mizzle
LRV 52

Mizzle is the lighter choice

Agreeable Gray
Charcoal Slate
Agreeable Gray
Sherwin-Williams
Agreeable Gray
LRV 60

Agreeable Gray is the lighter choice

Denim Drift
Charcoal Slate
Denim Drift
Dulux
Denim Drift
LRV 27

Denim Drift reads noticeably lighter

Tranquil Dawn
Charcoal Slate
Tranquil Dawn
Dulux
Tranquil Dawn
LRV 55

Tranquil Dawn is the lighter choice

Balboa Mist
Charcoal Slate
Balboa Mist
Benjamin Moore
Balboa Mist
LRV 66

Balboa Mist is the lighter choice

Vintage Vogue
Charcoal Slate
Vintage Vogue
Benjamin Moore
Vintage Vogue
LRV 12

Nearly identical in tone

Pale Green
Charcoal Slate
Pale Green
RAL ClassicClassic
Pale Green
LRV 31

Pale Green reads noticeably lighter

Pine Needle
Charcoal Slate
Pine Needle
Dulux
Pine Needle
LRV 7

Charcoal Slate reads slightly lighter

Cement grey
Charcoal Slate
Cement grey
RAL ClassicClassic
Cement grey
LRV 24

Cement grey reads slightly lighter

Black grey
Charcoal Slate
Black grey
RAL ClassicClassic
Black grey
LRV 6

Charcoal Slate reads slightly lighter

Piazza
Charcoal Slate
Piazza
Tikkurila
Piazza
LRV 65

Piazza is the lighter choice

Humble Yellow
Charcoal Slate
Humble Yellow
Jotun
Humble Yellow
LRV 57

Humble Yellow is the lighter choice

Windmill Lane
Charcoal Slate
Windmill Lane
Little Greene
Windmill Lane
LRV 31

Windmill Lane reads noticeably lighter

Senses
Charcoal Slate
Senses
Jotun
Senses
LRV 41

Senses is the lighter choice

Lamp Black
Charcoal Slate
Lamp Black
Little Greene
Lamp Black
LRV 3

Charcoal Slate reads slightly lighter

Washed Linen
Charcoal Slate
Washed Linen
Jotun
Washed Linen
LRV 55

Washed Linen is the lighter choice

Tea with Florence
Charcoal Slate
Tea with Florence
Little Greene
Tea with Florence
LRV 18

Tea with Florence reads slightly lighter

Thames Fog
Charcoal Slate
Thames Fog
Valspar
Thames Fog
LRV 27

Thames Fog reads noticeably lighter

Ocean Abyss
Charcoal Slate
Ocean Abyss
Behr
Ocean Abyss
LRV 7

Charcoal Slate reads slightly lighter

Classic Silver
Charcoal Slate
Classic Silver
Behr
Classic Silver
LRV 48

Classic Silver is the lighter choice

Teton Blue
Charcoal Slate
Teton Blue
Behr
Teton Blue
LRV 31

Teton Blue reads noticeably lighter

RAL 110-2
Charcoal Slate
RAL 110-2
RAL EffectEffect
RAL 110-2
LRV 72

RAL 110-2 is the lighter choice

RAL 110-1
Charcoal Slate
RAL 110-1
RAL EffectEffect
RAL 110-1
LRV 80

RAL 110-1 is the lighter choice

Paper
Charcoal Slate
Paper
Tikkurila
Paper
LRV 88

Paper is the lighter choice

Passageway
Charcoal Slate
Passageway
Valspar
Passageway
LRV 14

Nearly identical in tone