Dogs are completely colorblind and see the world only in shades of grey.
Dogs have dichromatic colour vision, meaning they see colours but differently than humans. They see blues and yellows well but reds and greens appear more muted or grey. Dogs can distinguish between these colours but with less colour saturation than humans. Their vision has evolved to prioritize motion detection and night vision over colour.
Reception
Sources
- Dog Vision - Wikipedia PRIMARY
- Snopes: Dogs See in Black and White REFERENCE