Dog Food Transition Schedule Calculator
Build a day-by-day schedule for switching your dog (or cat) to a new food — 7-, 10- or 14-day gradual mixes with the exact grams of old and new food per meal from your daily amount and meal count, dated from your start day, with what to do if stools loosen.
How it works
new food per day = daily ration × step % · old food per day = old ration × (100 − step %) · per meal = per day ÷ meals · 7-day steps: 25 / 50 / 75 / 100% (2, 2, 2, 1 days)
The bacteria in a dog's gut are adapted to the food it has been eating, and an abrupt change in protein source, fat level or fibre outruns their ability to adjust, producing the loose stools and gas that put owners off new foods. Blending the two over a week lets the microbiome shift gradually, and the quarter steps are simply a schedule anyone can measure with a kitchen scale. Sensitive dogs, big formula changes such as kibble to raw, and prescription diets benefit from a longer ramp, and the right response to trouble is to pause at the current mix rather than push through or give up.
Worked example
A dog on 300 g a day in two meals, starting Monday: days 1–2 get 113 g old + 38 g new per meal (25% new), days 3–4 75 g + 75 g, days 5–6 38 g + 113 g, and day 7 is 150 g of the new food per meal. You need about 900 g of the old food and 1,200 g of the new to see the week through.
Frequently asked questions
Can I switch cold turkey if the old food ran out?
You can, but expect a few days of soft stool. Feed slightly smaller meals, add a spoonful of plain pumpkin or a probiotic, and avoid treats until things settle. A same-brand, same-protein switch is usually tolerated.
Does this work for cats?
Yes, but cats are more stubborn about new textures: go slower (10–14 days), warm wet food slightly, and never let a cat go more than a day without eating — fasting risks hepatic lipidosis.
Related calculators
General veterinary guidance and rules of thumb (WSAVA / AAHA nutrition and reproduction references). Every animal differs — confirm feeding amounts, pregnancy timing and any concern with your veterinarian, especially for kittens, puppies, seniors and animals with medical conditions.