Evidence checked: Rabbit Welfare Association & Fund, RSPCA, House Rabbit Society, PDSA and the Merck Veterinary Manual · Reviewed August 2026 · Educational information for rabbit owners, not veterinary advice or a diagnosis.
Rabbit Calculators
Rabbits are prey animals and hide illness until they are already very unwell, so small shifts in weight, appetite, droppings or living space matter more than they would in a dog or cat. These seven tools turn everyday rabbit questions into plain estimates you can act on, covering age, weight, food, enclosure size, vaccination planning, running costs and day-to-day care. Every result is an educational starting point to discuss with a rabbit-savvy vet, never a substitute for one.
Rabbit Age Calculator
Convert a known or estimated birth date into your rabbit's current age and the broad life stage that goes with it. Pet rabbits commonly live eight to twelve years, and age changes how closely you watch teeth, weight and mobility. There is no validated way to convert rabbit years into human years, so this tool does not try.
Calculate Rabbit Age →Rabbit Weight Calculator
Log weights over time and read them alongside hands-on body condition scoring, where you feel the ribs, spine and hips rather than judging by sight. Adult rabbits range from under one kilo to over seven, so the useful signal is the direction your own rabbit is moving in, not a breed target.
Track Rabbit Weight →Rabbit Food Calculator
Work out roughly what the widely used hay, leafy green and pellet split looks like for a rabbit of your rabbit's weight. Unlimited feeding hay or growing grass does the heavy lifting; the pellet portion is the small, weighed part. Portions still need adjusting to body condition and vet advice.
Estimate Rabbit Food Portions →Rabbit Enclosure Calculator
Measure your hutch, pen, shed or room and compare it against published welfare space guidance, which is based on a single continuous ground footprint rather than total floor area. The tool shows why upper decks, tunnels and connected runs count as enrichment but not as base space.
Plan Rabbit Enclosure Size →Rabbit Vaccine Schedule
Build a personal checklist of what your rabbit has already had and what looks due, so nothing is missed between appointments. Which diseases are vaccinated against, and how often, differs by country and local outbreak risk, so the output is a planning aid to hand to your vet.
View Rabbit Vaccine Schedule →Rabbit Care Guide
The written companion to the tools: companionship and neutering, litter training, grooming and nail care, dental health, safe handling, and the seasonal risks that catch owners out, including flystrike in warm weather and cold, damp housing in winter. Read this first if you are new to rabbits.
Read Rabbit Care Guide →Rabbit Cost Calculator
Add up setup and ongoing spending using prices you enter yourself, across housing, hay and bedding, greens, neutering, vaccinations, insurance and an emergency vet fund. No prices are built in, because they vary widely by country, and rabbits are a commitment measured in years rather than months.
Estimate Rabbit Cost →Choosing the right calculator
If you are still deciding whether to get rabbits, start with the cost tool and the space tool. Both answer the questions people most often get wrong before adoption, and both are easier to face now than after the rabbits arrive.
If you already have rabbits and something feels slightly off, weight and food come first. Weight loss and falling hay intake are usually the earliest measurable signs that something has changed, and they often show up before behavior does.
If you are organizing veterinary care, pair the age tool with the vaccination planner. Age sets how often a health check is sensible, and the planner turns a vague sense of being overdue into a dated list you can read out at the clinic.
What these estimates can and cannot tell you
Every number here is an estimate built from published owner guidance, not a measurement of your individual rabbit. Domestic breeds vary enormously in adult size, and welfare bodies themselves note that general feeding guidelines will not suit every rabbit in every situation.
A calculator cannot look in a rabbit's mouth, feel an abdomen, take a temperature or run bloodwork. Dental spurs, gut pain and early kidney disease are all invisible to a form on a screen, and all are common reasons a rabbit stops eating.
Vaccination is the clearest example of why local advice wins. Available vaccines, the diseases they cover and booster frequency differ between countries and change as strains spread, so treat any schedule as a prompt to ask, not an instruction to follow.
Urgent warning signs in rabbits
Rabbits deteriorate faster than most owners expect. Treat the following as reasons to contact an emergency or rabbit-savvy vet straight away, at any hour, rather than waiting to see whether things improve overnight.
- Not eating, or passing few or no droppings. A gut that slows or stops is painful and can be fatal. House Rabbit Society treats twelve hours without food or droppings as an emergency, and many rabbit vets ask to be called within a few hours of a rabbit refusing food.
- Breathing trouble. Fast, labored or open-mouthed breathing, or breathing with the head stretched upward. Rabbits breathe through the nose, so mouth breathing is always serious.
- Collapse or sudden weakness. Unable to stand, unresponsive, fitting, or a sudden loss of use of the back legs.
- Severe or continuing bleeding from any wound, or blood you cannot account for.
- Suspected heatstroke. Very hot ears, rapid shallow breathing, drooling, wetness around the nose, lying flat and unwilling to move on a warm day. Move the rabbit somewhere cool and shaded, use a cool damp towel, and phone the vet immediately. Do not pour water over a rabbit or immerse it in cold water, as sudden cooling can cause shock.
- Flystrike. Fly eggs or maggots on the skin, usually around the back end. This is a same-hour emergency, and in warm weather the back end should be checked at least twice a day.
- Obvious pain. Sitting hunched and still, grinding teeth loudly, pressing the belly into the floor, or a hard, swollen abdomen.
- Head tilt, circling or loss of balance appearing suddenly.
These signs are reasons to seek help. They are not diagnoses, and several of them have more than one possible cause, which is precisely why they need examining rather than searching.
When to contact a rabbit-savvy vet
Book a routine appointment, rather than an emergency one, for gradual weight change, softer or fewer droppings, uneaten caecotrophs stuck to the fur, a persistently dirty back end, drooling or wet chin, overgrown nails, weepy eyes, or a rabbit that has simply become quieter than usual.
Preventive visits matter more in rabbits than many owners realize. A vaccination appointment is also the moment a vet checks teeth, weight and body condition, which is often how dental disease is caught before it stops a rabbit eating.
Find your rabbit vet before you need one. Not all small animal practices see rabbits confidently or open out of hours for them, and the Rabbit Welfare Association & Fund maintains a directory of practices that meet its standards. Save the number and the nearest out-of-hours address somewhere you can reach in a hurry.
Sources and further reading
Guidance on this page is drawn from the following organizations. Where their advice differs by country, follow the source relevant to where you live and confirm with your own vet.
- RWAF: minimum space recommendations and how to feed rabbits
- RWAF: gut slowdown emergency guidance and RWAF vaccination advice (UK)
- RSPCA: pet rabbits and RSPCA: rabbits in hot weather
- RSPCA Australia Knowledgebase: heat stress in rabbits
- Merck Veterinary Manual: routine health care of rabbits
- House Rabbit Society: GI stasis and rabbit diet and nutrition
- PDSA: heatstroke in rabbits
This page is educational and does not diagnose, treat or prescribe. If you are worried about a rabbit right now, contact a rabbit-savvy or emergency vet rather than reading further.