Dog vision: the science and the numbers
Canis familiaris · order Carnivora · Mammals: all the numbers
Dogs have 2 colour receptor classes (431 and 555 nm): mainly blues and yellows; reds and greens look alike.[1] Their sharpest vision resolves 8.3 cycles per degree, against 63.75 for people in this dataset.[5] Their eyes cover about 250° with 75° seen by both eyes; a reflective layer (tapetum) helps in dim light.[10]
- 2colour receptor classesMeasured*
- 8.3cycles per degree (sharpness)Measured*
- 250°field of viewMeasured*
- 77.5hertz flicker fusion (motion)Measured*
The dog (Canis familiaris) is a mammal in the order Carnivora. Its eyes belong to the vision type Day dichromat mammal: two cone types (blue and yellow, so reds and greens merge), moderate sharpness and a horizontal band of sharp vision. Measured in this species: colour, sharpness, field of view, foveas, night vision and motion (flicker fusion). Measured core: measured values on at least 3 of the 6 dials.
This is a simulation built from published eye measurements, not what the animal experiences.
What dogs see: colour receptors
What stands out
- It has two colour receptor classes (a dichromat): reds and greens fall on one axis, as in red-green colour blindness in people.
- Its sharpest vision resolves 8.3 cycles per degree: the finest stripe pattern it can tell apart from grey.
- Its eyes cover about 250° around the head, with 75° seen by both eyes at once.
- It stops seeing flicker at 77.5 Hz, against 60 Hz for people in this dataset, so fast motion looks about 1.3 times slower to it.[23][24]
- Activity pattern: cathemeral.
The six dials
Evidence levels: how the tiers work. "Measured" means a value measured in this species; "Estimated" values come from a close relative or an eye-size formula. The last column gives the values for people from the same catalogue.
| Dial | Value | Evidence | Sources | People |
|---|---|---|---|---|
| Colour | Colour receptors 2 receptor classes: 431 nm (VS/SWS (violet)), 555 nm (LWS (long)) measured in this species | Measured (not re-verified) | [1] | Colour receptors: 3 receptor classes: 421.5 nm (VS/SWS (violet)), 532 nm (MWS (green)), 558.4 nm (LWS (long)) Measured (not re-verified)[1][2][3][4] |
| Sharpness | Acuity 8.3 cycles per degree median of 1 anatomical-ganglion rows (method priority rule) | Measured (not re-verified) | [5] | Acuity: 63.75 cycles per degree Measured[6][7] |
| Field of view | Binocular overlap 75° median of 1 rows (eyes-at-rest rows preferred) | Measured (not re-verified) | [5] | Binocular overlap: 122.5° Measured[8][5] Total field of view: 200° Measured (not re-verified)[9] Blind area behind the head: 160° Derived[9] Eye placement: frontal Derived[8][5] |
| Total field of view 250° species-v1.csv | Measured (not re-verified) | [10] | ||
| Blind area behind the head 110° blind area = 360 - total field | Derived | [10] | ||
| Eye placement frontal frontal if binocular overlap >= 60 deg, else lateral | Derived | [5] | ||
| Sharp zones (foveas) | Number of foveas 0 fovea_present / area_centralis_type (retinal topography; count 1 = fovea present, 0 = none) | Measured | [11] | Number of foveas: 1 Measured[11] Fovea type: fovea Measured[11] |
| Fovea type area centralis, horizontal streak | Measured | [11] | ||
| Night vision | Activity pattern cathemeral mode of 3 rows (of 3 rows): cathemeral; mesopic | Measured (not re-verified) | [1][12] | Activity pattern: diurnal Measured (not re-verified)[13][14][15][1][16][17][12][18] Pupil shape: vertical Group default[19][20] Reflective layer (tapetum): no Measured[21] Rods vs cones: cone-dominated Derived[13][14][15][1][16][17][12][18] |
| Pupil shape circular | Estimated | [19] | ||
| Reflective layer (tapetum) yes | Measured | [22] | ||
| Rods vs cones mixed nocturnal -> rod-dominated; crepuscular / cathemeral / mixed -> mixed; diurnal -> cone-dominated | Derived | [1][12] | ||
| Motion (flicker fusion) | Flicker fusion frequency 77.5 Hz median of 2 bright-light rows (behavioural/whole-eye ERG rows; all rows: [75.0, 80.0]) | Measured (not re-verified) | [23][24] | Flicker fusion frequency: 60 Hz Measured[23][24] |
All mammals side by side: Mammals: every measurement. Method: how we know what animals see.
Sources
- Longcore 2023
- Kirwan
- Müller et al. 2009
- Thermal Activation and Photoactivation of Visual… 2004
- Heffner et al. 1992
- Kirk et al. 2004
- Veilleux et al. 2014
- Heesy 2004
- Campbell & Green 1965
- Miller & Murphy 1995
- Kopania et al. 2025
- Schmitz et al. 2011
- Anderson et al. 2017
- Borges et al. 2018
- Wilman et al. 2014
- Maor et al. 2017
- Jones et al. 2009
- Moura et al. 2024
- Banks et al. 2015
- Cervino et al. 2021
- Guareschi et al. 2025
- Schwab et al. 2002
- Healy et al. 2013
- Inger et al. 2014
Every value cites its sources (all sources). Values were extracted from these works and converted (units, medians, derived values); changes are ours, and the listed sources do not endorse this site. Data: catalogue-v1, built 2026-09-29. Accuracy notes: how accurate is this? Method: how we know.