Color spec
| Brand | Glidden |
| Name | Mountain Slate Blue |
| SKU | 10BB 18/106 |
| Hex | #687788 |
| RGB | 104, 119, 136 |
| HSL | 212°, 13%, 47% |
| LRV | 18 |
| Undertone | cool blue tone |
| Family | Blue |
About Glidden Mountain Slate Blue
With an LRV of 18, Mountain Slate Blue is a deep, dramatic shade. It soaks up light in north-facing rooms and looks richest where strong daylight hits it. Its blue undertone is the part to watch: it gets picked up by whatever sits next to it, so test it against your trim, floor and the room's main light before committing. Warm artificial light softens it; cool LED can make it look flat, so match your bulbs to the mood you want.
Mountain Slate Blue works best as a feature — a single wall, built-ins, a study or dining room — rather than wrapping a whole bright space. Blues calm a room, which makes them popular in bedrooms, bathrooms and home offices.
Closest matches by brand
12 brands within ΔE 5The closest matches per brand by ΔE2000, computed against each brand's full deck. Only colors within ΔE 5 (close enough to substitute on a wall) are shown — brands with no real match are left off. Tap any swatch for its full single-color spec; tap the brand title to browse all blue from that brand.
Behr
Benjamin Moore
Valspar
PPG / Glidden
Dutch Boy
Dunn-Edwards
Diamond Vogel
Hirshfield's
Rodda
C2 Paint
Backdrop
Kompozit
Similar Glidden colors
closest in the Glidden deckThe nearest shades to Mountain Slate Blue within Glidden's own range, ranked by perceptual color distance — useful when you want the same look a touch lighter, darker, or warmer.
Coordinated palette
Generated by hue-rotating #687788 in HSL space. Pair Mountain Slate Blue with one accent and one neutral — the swatches below are starting points, not final picks.
Accessibility (WCAG contrast)
WCAG 2.1: AA = 4.5:1 normal text · AA Large = 3:1 large text · AAA = 7:1 normal text.
Glidden Mountain Slate Blue Equivalents at Other Brands
Matching Mountain Slate Blue from a different paint counter? Below is the single closest color in each major US deck and how close it really is. Remember that any paint store can also custom-tint Glidden 10BB 18/106 directly — these equivalents are for when you'd rather stay inside one brand's own deck.
Behr Equivalent of Mountain Slate Blue
Behr's nearest match is Always Indigo (ECC-57-3), visually identical in normal room light (ΔE 1.59). It sits at the same lightness (LRV 18 vs 18) and carries a cool blue undertone, so it substitutes for Mountain Slate Blue without repainting risk. See the full Always Indigo swatch →
Benjamin Moore Equivalent of Mountain Slate Blue
Benjamin Moore has no exact twin of Mountain Slate Blue. The nearest is Stillwater (1650) at ΔE 4.04 — close, but the difference shows next to trim and in side light. It sits at the same lightness (LRV 19 vs 18). Compare large swatches before substituting. See the full Stillwater swatch →
Valspar Equivalent of Mountain Slate Blue
At Valspar, the closest color to Mountain Slate Blue is Seattle Haze (4003-4B) — very close at ΔE 2.47, though not an exact twin. It sits at the same lightness (LRV 17.9 vs 18) and carries a cool blue undertone; sample both side by side if the room gets strong natural light. See the full Seattle Haze swatch →
PPG / Glidden Equivalent of Mountain Slate Blue
PPG / Glidden's nearest match is License To Dream (PPG10-22), visually identical in normal room light (ΔE 1.87). It sits at the same lightness (LRV 17 vs 18) and carries a cool blue undertone, so it substitutes for Mountain Slate Blue without repainting risk. See the full License To Dream swatch →
Diamond Vogel Equivalent of Mountain Slate Blue
Diamond Vogel's nearest match is Blue Depths (0626), visually identical in normal room light (ΔE 1.95). It sits at the same lightness (LRV 18 vs 18) and carries a cool blue undertone, so it substitutes for Mountain Slate Blue without repainting risk. See the full Blue Depths swatch →
Rodda Equivalent of Mountain Slate Blue
At Rodda, the closest color to Mountain Slate Blue is Evening Tide (R088) — very close at ΔE 2.94, though not an exact twin. It sits at the same lightness (LRV 18 vs 18) and carries a cool blue undertone; sample both side by side if the room gets strong natural light. See the full Evening Tide swatch →
C2 Paint Equivalent of Mountain Slate Blue
C2 Paint has no exact twin of Mountain Slate Blue. The nearest is Mistral (C2-791) at ΔE 3.94 — close, but the difference shows next to trim and in side light. It sits at the same lightness (LRV 17 vs 18). Compare large swatches before substituting. See the full Mistral swatch →
Backdrop Equivalent of Mountain Slate Blue
Backdrop has no exact twin of Mountain Slate Blue. The nearest is Mom Jeans (BD-MJ) at ΔE 4.49 — close, but the difference shows next to trim and in side light. It sits at the same lightness (LRV 18 vs 18). Compare large swatches before substituting. See the full Mom Jeans swatch →