Dog · Large Breed
Collie Age Calculator
Use this Collie age calculator to convert dog years to human years. You can also check the average Collie lifespan, adult weight range, growth chart, feeding guide, and breed facts in one place.
Quick Answer
Collie facts at a glance
Average lifespan
12-14 years
Adult weight
18-34 kg
Fully grown
15-18 months
The Calculator
How old is your Collie in human years?
At 1 year old
Your Collie is approximately 18 in human years.
Field Notes
Collie Lifespan, Size, and Care
Collies originated in Scotland and northern England, where they were bred as hardworking sheepdogs capable of managing flocks over rough terrain. Over time, they became popular beyond farm life because of their elegance, intelligence, and dependable nature. The breed is most commonly seen in two coat varieties, Rough and Smooth, which share the same general temperament and structure.
In temperament, Collies are usually sweet, devoted, and emotionally attuned to their people. They tend to learn quickly and respond best to calm, positive training rather than harsh correction, as many are sensitive by nature. Most Collies are friendly or politely reserved with strangers and generally do well in family settings when socialized early.
Care for a Collie includes routine veterinary visits, attention to dental health, and a balanced diet that supports lean body condition. Because some Collies can carry the MDR1 gene mutation, owners should inform their veterinarian before medications are prescribed. Mental stimulation is also important, since this breed thrives when given training games, problem-solving activities, and opportunities to use its working mind.
Exercise needs are moderate to fairly high, and Collies usually do best with daily walks plus active play, training sessions, or time in a secure yard. They are not typically as intense as some other herding breeds, but they still need consistent physical and mental outlets to prevent boredom. Many Collies enjoy hiking, obedience, rally, herding activities, and interactive family routines.
Temperament
Exercise Needs
moderate
Health Watch
- Collie eye anomaly (CEA)
- Progressive retinal atrophy (PRA)
- Dermatomyositis
- MDR1 drug sensitivity
- Hip dysplasia
Grooming
Rough Collies need thorough brushing several times a week to prevent mats and manage shedding, while Smooth Collies require less coat care but still benefit from regular brushing.
Growth Curve
Collie weight chart
Typical weight progression from young to adult. The tinted band marks the healthy adult range. 18-34 kg.
Nutrition, Staged
Collie Feeding Guide
Use this Collie feeding guide as a starting point for common life stages, then adjust for body condition, activity, and veterinary advice.
Formative years
Young
Feed a complete growth formula in 3 to 4 measured meals per day, adjusting portions to body condition, expected adult size, and the food label. Choose a formula appropriate for the puppy's projected adult size, growth rate, and veterinary guidance.
Peak years
Adult
Feed a complete adult diet in measured meals, usually split into 2 feedings per day, and adjust the portion to weight, activity level, and body condition. Recheck portions whenever exercise, treats, or neuter status changes.
Mature years
Senior
Use a senior or calorie-controlled diet when weight gain, lower activity, or age-related conditions appear, and monitor appetite, stool quality, and muscle mass closely. Smaller measured meals can help if dental disease, digestive sensitivity, or medication schedules change the routine.
Questions, Answered
On the Collie
That depends on the pet's actual age. Use the calculator above to estimate a Collie's age in human years using the method shown on this page.
Most Collies live 12-14 years, although genetics, diet, body condition, husbandry, and preventive care all influence the real outcome.
A full grown Collie usually weighs 18-34 kg, though sex, lineage, and body condition can move an individual above or below the average range.
Most Collies are close to full size around 15-18 months, although growth rate and final build vary from one pet to another.
Use the feeding guide above as a starting point, then adjust for age, body condition, activity, and your veterinarian's recommendations.
Yes, Collies are widely regarded as excellent family dogs because they are gentle, loyal, and usually very patient with children. They tend to form close bonds with their household and often do best when included in daily family life rather than left alone for long periods.
Collies can be vocal, especially if they are bored, alerting to visitors, or reacting to activity around the home. With enough exercise, training, and mental stimulation, most can learn when barking is appropriate and when to settle quietly.
Collies are generally very trainable because they are intelligent and eager to work with people. They usually respond especially well to positive reinforcement, consistency, and gentle handling, while harsh methods may make them anxious or shut down.
Most Collies need at least one to two good walks a day along with play, training, or another mentally engaging activity. They are active dogs but not always extreme in energy, so a balanced routine of movement and interaction is usually enough to keep them happy.
Prospective owners should ask about eye testing, hip evaluations, and genetic screening, especially for MDR1 sensitivity and inherited eye conditions. Early screening helps identify risks sooner and allows veterinarians and breeders to make better decisions about medication safety and long-term care.
Adjacent Breeds
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