How much should I be feeding my small dog? — body condition is the answer the chart can’t give

A small-breed parent on a forum describes how she feeds: she goes by how her dog’s body looks. Not by the bag’s chart. Not by the gram-by-gram routine most of the category ships with. By what her dog’s body has been telling her, week to week, over months.

Here’s how that read works — and where the calculator fits in alongside it. Because the answer to how much should I be feeding my small dog isn’t one or the other. It’s both, in a particular order.

How much should I be feeding my small dog?

Start with a good calculator; finish at the body. The TENDS feeding calculator uses an FEDIAF-aligned MER model, scales by metabolic body weight (BW⁰·⁷⁵ — the unit the canine literature backs up), and is set to the metabolizable energy of this specific food. The activity-level spread alone moves daily intake roughly 84% across the calm-to-very-active range. The dog tells you the rest.

How do I know if I’m feeding the right amount?

Body condition is what finishes any starting point. You read it by feel and by eye together — feel the ribs (you should find them with light pressure, not buried, not poking out); look for the tuck behind the ribs and the waist from above. Body condition is scored from 1 to 9; 4 to 5 is the lean-but-not-thin range most small adults sit best in. How she’s trending across weeks matters more than any single check. Your dog at month two tells you whether the starting point is fitting.

What is body condition score in dogs?

It’s a standard vet read that pulls rib feel, waist, and belly tuck together into a 1–9 scale (some scales run 1–5). Lean, ribs you can feel cleanly under light pressure: that reads as 4–5. Ribs buried in fat read upward; ribs you can see without pressing read downward. The score isn’t a judgement on you — it’s a way to catch what the bathroom scale misses, especially for small dogs, where the changes in total weight look tiny on the dial.

Should I trust the bag’s chart for portion size?

As a starting point, yes. As the final word, no. The bag’s chart is a population average — set for a generic adult dog of a given weight class, with assumed activity, neuter status, and surroundings. The TENDS calculator does meaningfully more, and the body-condition read still finishes either one. The chart wants a number. The dog has been telling you whether the number is fitting.

What a chart actually is

A bag’s portion calculator is a population average. The chart’s job is to give you a starting point. That’s a real and useful job.

The TENDS feeding calculator does meaningfully more than a generic bag chart. It uses an FEDIAF-aligned maintenance energy model. It scales by metabolic body weight (BW⁰·⁷⁵ — the unit the canine literature actually backs up), not by raw kilograms or breed assumptions. It’s set to the metabolizable energy of this specific food (3.827 kcal/g, derived from laboratory analysis of the finished product). And it adjusts for activity level across a calm-to-very-active range, with weight-management adjustments built in.

It’s the best starting point you can get.

But even the best starting point is still a starting point.

What a calculator does well, and where it stops

TENDS built its calculator to be the best starting point because parents deserve the math done properly. The math itself isn’t the thing to fix here. The thing is what the math can and can’t finish.

Take the activity adjustment on its own. Across the calmest-to-most-active range the calculator carries, daily intake for a 5 kg dog moves from roughly 263 g/day (low activity) to roughly 336 g/day (very high activity) — a range of about 84%. That’s not a rounding margin. That’s a real spread, and your dog sits somewhere on that curve that’s specific to her life, not to her species. Even inside the best starting point, the variation is big.

The only way to know which point on the curve fits this dog, in this home, is to read what her body says back over weeks. Body condition is what finishes any starting point — including this one.

What body condition actually reads

Body condition is the whole-picture sign your dog has been carrying, week to week, in response to what’s been arriving in the bowl. Three layers, all of them simple to read at home.

Look. Stand above her and look down. There should be a clear waist behind the ribs — narrower at the waist than at the ribcage. No waist (a straight or rounded line from ribs to hip) reads over. A waist that dips in sharply reads under. Then crouch to her level and look at the belly tuck from the side — the underline should rise a little behind the ribcage, not hang straight or sag down.

Feel. Put your hands lightly on her ribcage, light pressure only. You should feel the ribs easily, with a thin layer of fat over them — like feeling the back of your own hand through a thin glove. If you have to press hard to find ribs, that’s over. If you can see ribs without any pressure, or they feel sharp under your fingers, that’s under.

Track it over time. Body condition shows over months, not weeks. The photo practice walks you through it — same lighting, same angle, same time of day, monthly. Your dog at month three doesn’t look much different from month two. But your dog at month three next to month zero shows you the change that day-to-day looking couldn’t hold.

Reading all three together is the answer. No single sign on its own is.

If her body condition is changing fast with no obvious food reason — sudden weight loss, sudden weight gain, lethargy, symptoms coming back again and again alongside it — that’s a vet conversation first. What we’re talking about here is the otherwise-well dog whose body condition is moving slowly, one way or the other, in response to what the household has been feeding.

The math underneath, and the math TENDS uses

The reason the calculator’s math works is that small dogs really do need more energy per kilogram than larger dogs — but the right unit for that math isn’t raw kilograms. It’s metabolic body weight: BW⁰·⁷⁵. A 2 kg dog needs roughly 40% more energy per kilogram than a 7 kg dog¹. The TENDS calculator scales accordingly.

A study tracking 586 real pet dogs found that when you calculate energy needs the right way, the formula works the same across all sizes. Small dogs and large dogs don't need different math — they need the same math done correctly. The common idea that small dogs need a completely different feeding approach doesn't hold up against the data. The body size is different. The unit changes. The formula doesn't.

TENDS shows the studies on which their calculator is built on. The science isn't in the background — it's the basis for everything on this page.

How the read works at home — the two-lever practice

First lever: use the calculator. Body weight, activity level, food. The TENDS feeding calculator will give you a personalised starting point — not a population average, not a single-weight-class generic chart, but a number set to your dog’s weight, your dog’s activity level, and the metabolizable energy of the food in the bowl.

Second lever: read her body condition over the next two to three weeks. The looking checks (waist from above, belly tuck from the side). The feel check (ribs under light pressure). And tracking it over time (a monthly body-condition photo, per the photo practice). Read all three together; no single one is the answer.

Adjust based on what her body says. If her body condition holds steady at the calculator’s starting point, the calculator landed for your dog. Hold. If she’s drifting over (waist disappearing; ribs harder to feel), cut the daily amount by 5–10% and read again in two to three weeks. If she’s drifting under (waist too sharp; ribs clearly visible), add 5–10% and read again in two to three weeks. The calculator is the math. The dog is the read. The two work together, in that order.

Where TENDS sits in this question

Superfood Blend is the food the calculator’s energy density is calibrated against — the math is specific to this product, not to a generic small-dog kibble. The feeding calculator is the first lever; body condition is the second. If the read turns up more than portion calibration — coat changing, energy changing, what comes out changing — the Hydration Ritual and the wider articles walk what those changes point to.

What the read gives back

The calculator is the most rigorous starting point. The dog is the destination.

Read the dog. Not the chart. The chart gives you a starting point. Your dog tells you whether it's working. Watch her — her energy, her coat, her stool, how she carries herself. That's the read that matters.