Free horse tools & calculators

Quick answers for horse owners, riders and yards: weights, due dates, feed, rugs, jabs and more. Free, no sign-up, and they work on your phone at the yard.

• Horse weight calculator — Estimate your horse's weight with a tape measure: enter heart girth and body length in cm or inches for an instant weight in kg and lb. Free, with how-to-measure guide.
• Foaling date calculator — Free mare foaling date calculator: enter the covering date to get the due date (340 days), the normal 320–370 day window, and dates for scans and vaccinations.
• Rider weight calculator — Free rider-to-horse weight calculator: rider plus tack as a percentage of your horse's bodyweight, checked against the 15–20% guideline, with the maximum load.
• Hay & forage calculator — Free horse hay calculator: daily forage from bodyweight, then hay per week and bales for the whole winter, for one horse or a yard. Allows for grazing and bale size.
• Rug weight guide — Which horse rug tonight? Enter the overnight low, clip and whether your horse is stabled or out for a suggested rug weight in grams. Free UK rugging chart.
• Flu vaccination checker — Check your horse's equine flu vaccination dates against FEI, British Equestrian, USEF or racing rules: primary course, boosters, competition windows and when the next jab is due.
• Worming planner — Plan a year of targeted horse worming: faecal egg counts, tapeworm tests in spring and autumn, encysted redworm in winter, plus a dose-by-weight helper.
• Grazing & paddock calculator — How many horses per acre? Check your grazing against UK, US or Australian guidance and plan a paddock rotation with days on and rest. Free acres or hectares calculator.
• Horse trailer towing calculator — Can my car tow a horse trailer? Check the laden trailer against its plated maximum, your towing limit and train weight, plus licence rules for the UK, EU, US, Canada, Australia and NZ.
• Cost of keeping a horse — How much does a horse cost per month? Add up livery or board, hay, feed, bedding, farrier, vet, insurance and extras for a monthly and yearly total. Free horse cost calculator.
• Hands to cm converter — Convert horse heights between hands, inches and centimetres both ways. 15.2 hh = 157.5 cm. Free converter with a table of common heights and how to measure.
• Horse age in human years — How old is your horse in human years? Enter a date of birth for the exact age and next birthday, or an age for a rough human-years comparison and life stage.
• Dressage score calculator — Turn your dressage test marks into a percentage: movements, coefficients, collective marks and errors of course, with penalties for British Dressage, FEI, USEF and more. Free.

These tools are made by Horsepower, the yard and stable management app. To keep these numbers for every horse, with reminders when things are due, it's free for up to 3 horses.