Acier → Valspar
The closest Valspar matches for Sherwin Williams Acier (SW 9170-2), ranked by perceptual color distance.
Finding a Valspar Equivalent for Acier
If you love Sherwin Williams Acier but need a Valspar alternative, you are not alone. This is one of the most common cross-brand paint matching searches, whether you are working with a painter who prefers Valspar, your local store does not carry Sherwin Williams, or you simply want to compare prices across brands before committing.
Acier (SW 9170-2) is a medium-dark gray with cool steel gray undertones. A cool, steely gray. Named for the French word for steel. Neutral and industrial. Between Magnetic Gray and Dovetail. To find a good Valspar match, we need a color that captures not just the right depth (LRV 25) but also that specific undertone character. That is where Delta E color science comes in.
We calculated the perceptual color distance between Acier and every Valspar color using the CIE2000 Delta E formula, which measures how different two colors look to the human eye. A Delta E under 2 means most people cannot tell the colors apart. Between 2 and 4, you might notice a difference in certain lighting. Above 5, the difference is clearly visible side by side.
The good news: there is a strong Valspar match for Acier. Cathedral Stone (VR082C) comes in with a Delta E of 2, which puts it in the "excellent match" range. Cathedral Stone is the closest Valspar option at LRV 25. Very close match.
Valspar Matches for Acier
Cathedral Stone is the closest Valspar option at LRV 25. Very close match.
| Acier | Cathedral Stone | |
|---|---|---|
| LRV | 25 | 25 |
| Hex | #9D9D9A | #9D9993 |
| Undertone | Cool Steel Gray | Warm Dark Gray |
| Family | Gray | Gray |
Undertone Comparison
Acier has cool steel gray undertones. A cool, steely gray. Named for the French word for steel. Neutral and industrial. Between Magnetic Gray and Dovetail.
Cathedral Stone has warm dark gray undertones. A warm, dark gray with stone-like undertones. Substantial and grounding, like the weathered stone of an old cathedral. More warm and earthy than a cool charcoal.
The undertone difference is worth paying attention to. While they are close in overall appearance, the different undertones mean they may diverge in certain lighting. Acier's cool steel gray quality may read differently than Cathedral Stone's warm dark gray character, especially in rooms with strong directional light or colored accents that could pull out one undertone more than the other. Test a sample in your specific room before committing.
How These Colors Behave in Different Lighting
Acier in Your Room
Cool and clean. A neutral gray that reads as steel in all conditions.
Cathedral Stone in Your Room
In bright light, the warm stone quality is visible. In dim rooms, it reads as a rich, warm dark gray. The warmth keeps it from feeling cold or industrial.
LRV and Brightness
Acier has an LRV of 25, while Cathedral Stone has an LRV of 25. These two colors reflect a very similar amount of light, so you should not notice a significant difference in room brightness when switching between them. The room will feel approximately the same in terms of light and space, which makes this a smoother transition.
Best Rooms for Acier
Sherwin Williams recommends Acier for: office, bathroom, hallway, accent wall, exterior. With an LRV of 25, this is a medium-dark color that is in the medium range, adding real depth and presence to a room. It works best in rooms with good natural light or as an accent wall color. In smaller or darker rooms, pair it with bright white trim to keep the space from feeling closed in.
Cathedral Stone is recommended for: accent wall, exterior, office, cabinets, front door. The recommended applications differ slightly between brands, but the color's properties should work in the same rooms regardless of which brand you choose. Trust the LRV and undertone data more than the specific room suggestions, and always test in your actual space.
Acier in Other Brands
Looking for Acier equivalents in other brands besides Valspar? We have matches across all major paint brands.
Frequently Asked Questions
The closest Valspar match for Acier (SW 9170-2) is Cathedral Stone (VR082C) with a Delta E of 2, which rates as a "excellent match" match. Cathedral Stone is the closest Valspar option at LRV 25. Very close match. Delta E measures perceptual color distance on a scale where under 2 means nearly identical, 2 to 4 means close with subtle differences, and over 5 means clearly noticeable.
No, they are not identical. Acier is a Sherwin Williams color with cool steel gray undertones and an LRV of 25. Cathedral Stone is a Valspar color with warm dark gray undertones and an LRV of 25. With a Delta E of 2, these are extremely close and most people will not spot the difference on a wall. Paint formulations differ between brands, so even colors with similar values can look slightly different due to pigment concentration, binders, and finish.
With a Delta E of 2, these colors are close enough to use in separate rooms of the same house without a jarring difference. However, avoid painting them on adjacent walls in the same room, as even subtle differences become apparent at a hard edge where two paints meet. For the smoothest result, use one brand consistently within each connected space and reserve the other brand for rooms that are visually separated.
There are several practical reasons to look for a Valspar equivalent. Price differences between brands can be significant on large projects. Availability matters if your nearest paint store or home center specializes in Valspar. Some painters have strong preferences for one brand's formula based on coverage, dry time, or workability. And if you are touching up existing Valspar work, matching within the same brand gives you the best consistency for seamless results.
Match calculations use Delta E (CIE2000) computed from Lab color space conversion. Color data sourced from manufacturer specifications. Last reviewed: March 22, 2026.