Daily Feeding, Calorie & Treat Calculator

Portion sizes by life stage, an estimated daily calorie need, a treat ceiling of 5% of calories, and an instant safety check of the foods your rats got today. Fancy rats are omnivores that do best on a lab-block base plus fresh vegetables and small amounts of protein.

Your Rat & Diet

Weight (g)

Age Stage

Activity Level

Staple Diet Type

Treats today (g, total)

Main Treat Type

Values are per rat, per day and update as you type. Adjust by body condition — you should be able to feel, but not see, the ribs.

Daily Portion Guide

Enter weight to see the daily portion split.

Calorie & Treat Budget

Estimated energy need (kcal/kg^0.75 × 110) and treat limit appear here.

Seed-Mix → Lab-Block Transition Plan

On a loose mix, rats selectively pick out oily sunflower seeds, peanuts and dried banana — the candy of the bowl — and leave the fortified pellets. This "selective feeding" leads to obesity alongside protein, calcium and vitamin deficiency. Mix the two diets and shift the ratio gradually over 4 weeks so gut flora adapts:

Week 1

75% seed mix
25% lab block

Week 2

50% seed mix
50% lab block

Week 3

25% seed mix
75% lab block

Week 4

100% lab block
seeds only as treats

Tip: serve the new block in the evening when rats are hungriest, and remove any mix left after ~20 minutes so they cannot keep cherry-picking.

Today's Food Safety Check

Tick everything your rat ate or was offered today. Any match produces an instant risk warning.

Foods to Avoid

Raw dry beans / raw peanuts — contain anti-nutrients (lectins); cook thoroughly before feeding.
Raw sweet potato, raw potato eyes/green parts — toxic alkaloids destroyed only by cooking.
Carbonated drinks — rats cannot burp effectively; gas buildup risks bloat.
Blue cheese / moldy foods — mold toxins are dangerous at their small body size.
Onion, garlic in large amounts — can damage red blood cells (hemolytic anemia).
Chocolate, caffeine, alcohol — toxic; even a crumb of dark chocolate is significant.
Grapes & raisins — suspected kidney toxicity; avoid entirely.
Citrus for males — d-limonene is linked to male rat kidney damage.
High-sugar / high-salt processed foods — obesity, diabetes and kidney strain.

Good daily staples: lab block (Oxbow/Mazuri-class), fresh leafy greens, broccoli, carrot, small fruit. Rotate proteins (cooked egg, cooked chicken, tofu) 2–3×/week. Split food into two meals and remove fresh leftovers within 12 hours.